[Semipermanent Highway Steel Bridges, 30-, 60-, and 90-Foot Spans]
[From the U.S. Government Publishing Office, www.gpo.gov]
to
WAR DEPARTMENT TECHNICAL MANUAL
SEMIPERMANENT
HIGHWAY STEEL BRIDGES
30-, 60-, AND 90- FOOT SPANS
WAR DEPARTMENT
Document Reserve
MTSU LIBRARY
MV1
2 7 JUNE 19 44
WAR DEPARTMENT TECHNICAL MA N UA L
T M 5-285
WAR DEPARTMENT, Washington 25, D. C., 27 June 1944.
TM 5-285, Semipermanent Highway Steel Bridges, 30-, 60-, and 90-foot Spans is published for the information and guidance of all concerned.
[A. G. 300.7 (17 May 44).]
By order of the Secretary of War:
G. C. MARSHALL,
Chief of Staff. Official:
J. A. ULIO,
Major General,
The Adjutant General.
Distribution:
As prescribed in paragraph 9a, FM 21-6; Armies (10); Corps (10); Sv C (10); Dept (10); C G, T of Opns (25); D (2); R & H 5 (5); IR 5 (5); I Bn 5 (5); IC 5 (15); Cs of Tech Sv (2); Arm & Sv Boards (2).
I R 5: T/O 5-21, Engr Gen Sv Regt.
I Bn 5: T/O & E 5-15, Engr Comb Bn; 5-75, Engr Cons Bn; 5-215, Annd Engr Bn; T/O 5-175, Engr Bn, Comb Regt; 5-415, Engr Avn Bn.
IC 5; T/O 5-26, Hq & Hq Det, Engr Bn, Engr Gen Sv Regt. For explanation of symbols, see FM 21-6.
SEMIPERMANENT HIGHWAY STEEL BRIDGES 30-, 60-, AND 90-FOOT SPANS
:W A R DEPARTMENT • 2 7 JUNE 1944
United States Government Printing Office Washington : 1944
CONTENTS
PART ONE
DESCRIPTION OF EQUIPMENT
CHAPTER 1
GENERAL
erection procedures including reconnaissance, organization of work, construction of abutments and supports, multiple spans, maintenance, repairs, and strengthening. Part Three consists of appendixes giving transportation and logistical data and lists of equipment. Part Four consists of numbered sheets showing general and detailed drawings needed for field erection.
PART ONE . DESCRIPTION OF EQUIPMENT Paragraphs
CHAPTER 1. GENERAL................................ 1-3
CHAPTER 2. PLANNING DATA.......................... 4-11
CHAPTERS. DESCRIPTION OF BRIDGES:
Section I. 30-foot I-beam bridge................12-14
II. 60-foot I-beam bridge..................15-17
III. 90-foot truss bridge................. 18-20
PART TWO . ERECTION
CHAPTER 4. RECONNAISSANCE AND PRELIMINARY PLANNING 21-27
CHAPTER 5. ORGANIZATION OF WORK................28-32
CHAPTER 6. CONSTRUCTION DETAILS COMMON TO ALL
BRIDGES...........................33-39
CHAPTER 7. ERECTION OF 30-FOOT BRIDGE..........40-44
CHAPTER 8. ERECTION OF 60-FOOT BRIDGE..........45-49
CHAPTER 9. ERECTION OF 90-FOOT BRIDGE:
Section I. General..............................50-51
II. Erection by launching single trusses...52-54
III. Erection by launching assembled bridge.55-58
IV. Removal of bridge.......................59-61
CHAPTER 10. MULTIPLE SPANS.........................62-65
CHAPTER 11. MAINTENANCE, REPAIRS, AND STRENGTHENING............................................... 66-69
Page
PART THR EE. APPENDIX, TABLES II TO XVIII..........48
PART FOU R. GENERAL AND DETAILED DRAWINGS ... 57
1. Scope of Manual
a. This manual describes and gives erection procedures for three semipermanent highway steel fixed bridges with wood floors. They are the 30-foot I-beam bridge (fig. 1), 60-foot I-beam bridge (fig. 2), and 90-foot truss bridge (fig. 3).
b. This manual is divided into four parts. Part One deals with planning data and description of equipment. Part Two covers
Figure 1. Partly decked 30-foot I-beam bridge showing type of construction. (The end dam on the near end is omitted to show details.')
2. Purpose of Bridges
The 30-, 60-, and 90-foot steel highway bridges are semipermanent structures intended primarily to replace tactical (or combat) bridges in lines of communication. The bridges may be used as single spans or may be combined into multiple spans with intermediate supports. Two-way traffic is accommodated by constructing parallel bridges.
3. References
For general information on bridge design and construction see FM 5-10. Typical designs of abutments and piers and construction methods under a variety of stream conditions are given in TM 5-286 (when published).
1
Figure 2. The 60-foot I-beam bridge with floor system, curbs, and end dam on near end omitted to show details.
Figure 3. The 90-foot truss bridge with flooring omitted to show details of the floor system. (Figure 50 shows bridge partly floored.)
2
CHAPTER 2
PLANNING DATA
4. Capacity
a. Posting Bridges. The normal posted capacity of all three bridges is 50 tons. These posted capacities are based on a unit-stress in tension of 24,000 pounds per square inch. It should be noted that these capacities and unit-stresses are considerably higher than the loads and unit stresses used in the design of the bridges (par. 11). Capacities are also based on the use of the laminated floor design shown on sheets 4 and 12, part IV.
b. Capacity Table. Table I gives the posted capacity of bridges and the U. S. weight class of vehicles that may cross with caution.
Table I. Capacity of bridges1
Bridge Posted capacity of bridge (tons) Maximum weight class of vehicle that may cross with caution 2 (tons)
30-foot 50 75
60-foot 50 75
90-foot 50 70
i Based on data furnished by Engineer Board.
Criteria used in computing capacity:
Maximum tensile stress in bending____________________________________ 24 000
Maximum compressive stress in bending______ ____ _____________ 24,000-7M> (y) 2
Maximum axial stress in tension, net section_________________________ 24,000
Maximum axial stress in compression _____________________ 22,500-^ )2
2 For definition of weight class see FM 5-10. With caution means one vehicle on bridge at one time, vehicle keeps on center line of bridge, speed not to exceed 5 mph, no breaking or shifting of gears.
5. Weights and Dimensions
A summary of weights and dimensions for the three bridges is given in table II. Data on packaging of materials is given in tables IV, V, VI.
6. Clearances
The width between curbs or guardrails for all bridges is 12 feet 6 inches, and the over-all width of deck is 14 feet 0 inches. The clearance inside to inside of trusses for the 90-foot bridge is 15 feet 4 inches.
7. Composition and Issue
a. Bridges. These bridges are stocked in depot. The material contained in one bridge set for one span is given in the bills of materials on sheets 1, 5, and 8. It should be noted that the bridge set does not
contain lumber for the timber floor. A detailed description of each bridge is given in chapter 3.
b. Erection Equipment. When necessary these bridges can be constructed with the organic equipment of general service regiments. However for expeditious construction it is essential that the equipment and materials listed in tables VII and VIII be drawn from depot. This equipment includes wire rope, wire-rope blocks, driftpins, large wrenches, and similar items for steel assembly. It is particularly important that a crane, preferably a /(-yard truck crane, be available for handling steel members.
c. Piers and Abutments. The type and materials used for construction of abutments or piers depends on the site and design selected and varies with local conditions. Material for abutments and piers must be requisitioned separately.
8. Erection Methods, Equipment, and Labor
See tables VII to XIII, inclusive. Additional detailed data and methods are given in part II.
9. Transportation
See table III.
10. Abutments and Piers
a. General. This manual does not give complete details on abutments and piers. Refer to FM 5-10 and TM 5-286 (when published) for this information. The typical designs of abutments and piers for these bridges given in TM 5-286 (when published) can be modified to fit local conditions.
b. Loads. Abutments and piers must be designed to accommo.date the loads given in table XIV.
11. Basis of Design
a. Loading. All three bridges were designed for a gross tank weight of 40 tons, assuming a ground-contact length of 13 feet, a track gauge (center to center of tracks) of 6 feet 11 inches, and a track width of 17 inches. In addition to the tank loading, the bridges were designed for the American Association of State Highway Officials (A. A. S. H. O.) H20 loading as given in the Standard Specifications for Highway Bridges, Thu-d Edition, 1941.
b. Material. (1) The design is based on the use of structural carbon steel conforming to A. S. T. M. Specification No. A 7-42, Steel for Bridges and Buildings (table XVII).
(2) The floors of the bridges were designed for creosoted lumber of 1800-pound stress-grade, rough sawn to the dimensions shown in the drawings, Part IV. If lumber of lower quality is used the floor construction must be modified accordingly. See table XT.VI, FM 5-10 (1944) for allowable working stresses in American and foreign woods.
c. Working Stresses. (1) The basic working unit-stresses used in designing the bridges are those given in the above-mentioned A. A. S. H. O. specifications increased 25 percent. Principal values used in the design are listed in table XVII.
(2) The basic working unit-stresses used in designing the timber floors are those given in the above-mentioned A. A. S. H. O. specifications. Principal values are given in table XVIII.
d. Curb. The 30- and 60-foot bridges are designed for a timber curb. Lumber for curb construction is not furnished with the bridge set, but the metal fastenings are included. The 90-foot bridge has a positive steel curb called a guardrail. The guardrail and metal fastenings are furnished with the bridge set.
e. Floor. The bridges are designed for a laminated timber floor fastened to the steel structure by metal floor clips. The laminated deck consists of 2- by 6-inch pieces placed on edge. Alternate floor designs are described in TM 5-286 (when published).
/. Bearings. The end bearings are designed for erection on ma-sonry, concrete, or timber supports.
g. Connections. All bridges are shop-fabricated by riveting and welding. All field connections are designed for structural ribbed bolts, with button or countersunk heads and hexagonal self locking nuts.
3
CHAPTER 3
DESCRIPTION OF BRIDGES
Section I
30-FOOT I-BEAM BRIDGE
12. Main Girders and End Bearings
a. Parts.
Mark
Description
Weight (pounds)
Gl_. BP1 AB1
Girder______________________________
Bearing plate_______________________
Anchor bolt_________________________
2, 554. 0
31. 0
4. 3
b. Girder. This bridge is built of four girders connected by steel diaphragms to form a rigid box-type structure (fig. 1 and sheet 2). The girders G1 are made of 24-inch, 74-pound wide-flange I-beams, 31 feet 6 inches long.
c. End Bearings. End bearings consist of a sole plate and a bearing plate BP1 (fig. 4). The sole plate is riveted to the end of the girder. The bearing plate rests on the sill or abutment seat. The sole plate rests on the bearing plate and during expansion or contraction of the bridge it slides on the bearing plate.
Figure 4- Bearing plate, traction clip, and protection angle for the 30-foot bridge.
INTERMEDIATE DIAPHRAGM
END DIAPHRAGM
Figure 5. Intermediate and end diaphragms for the 30-foot bridge. Diaphragms stiffen the bridge and distribute wtieet and track loads. (They are bolted to the girders at 10-foot intervals J
d. Anchor Bolt (fig. 6). The girders are held in place on the sills or abutment seats by anchor bolts AB1, 1 foot 6 inches long. These bolts are imbedded in the sills or abutment seat and extend through close fitting holes in the bearing plate and through slotted holes in the sole plate and lower flange of the girder. The slotted holes permit expansion and contraction of the girders with changes in temperature.
13. Bracing, Splices, and Fasteners
a. Parts.
Mark
Description
Weight (pounds)
DI___________________I Intermediate diaphragms_____________
D2___________________I End diaphragms______________________
| Bolts and nuts______________________
128
105 Variable
b. Diaphragms (fig. 5). Diaphragms placed between the girders at the ends of the bridge and at 10-foot intervals make the structure
rigid and distribute wheel or track loads among the girders. They serve also as lateral bracing (see sheets 2 and 3).
(1) Intermediate diaphragms Dl are %-inch steel plates to which 3- by 3- by %-inch angles have been shop-riveted at the top and bottom (fig. 5). Connection with the girders is made by field bolting the diaphragm to stiffener angles shop-riveted to the girders.
(2) End diaphragms D2 are 15-inch 33.9-pound channels connected to the girder at the ends of the bridge. Connections are the same as for intermediate diaphragms (fig. 5).
c. Bolts and Nuts (fig. 6). (1) Two types of bolts and nuts are used in this bridge:
(«) Machine bolts % inch in diameter with head and nut 1%6 inch square are used as erection bolts. They are used to draw parts together in a tight fit while structural ribbed bolts are being placed (fig- 6).
(6) Structural ribbed bolts % inch in diameter with button or countersunk heads and 1 %6-inch self-locking hexagonal nuts are used for all field connections (fig. 6). A structural ribbed bolt has a diameter slightly larger than the hole. When driven, the ribs on the bolt flatten and fill the hole, giving a tight fit and good bearing.
(2) See sheet 1 for detailed information on bolting.
14. Floor System
a. Parts.
Mark
Description
Weight (pounds)
Al___________________ Protection angle_______________________
Cl___________________ Traction clip__________________________
Flooring_____________________________
Curb_________________________________
42 8 Variable Variable
b. Flooring. The floor consists of plank treadways as a wearing surface on a laminated timber deck fastened to the girders by floor clips (see sheet 4).
(1) The laminated timber deck consists of 2- by 6-inch pieces 14 feet long set on edge across the girders. The pieces are nailed together with 50d cement-coated nails.
(2) Metal floor clips (fig. 6) fasten the timber deck to the steel girders. The floor clip is a 4- by 5-inch galvanized-steel plate provided with holes for nailing to the deck and notched to fit the flange of the girder (fig. 30).
(3) The treadway consists of 2- by 12-inch planks laid parallel to the direction of traffic.
c. Traction Clip (fig. 4). The traction clip Cl is a 5- by 5- by %-inch angle 7^ inches long bolted to each end of each girder. These clips prevent the timber deck from sliding on the girders.
d. Protection Angle (fig. 4). Protection angles Al are 5- by 3/2- by %6-inch angles 4'-10" long. They are installed over the flooring at the ends of the bridge to protect the flooring from excessive wear caused by vehicles passing on and off the bridge.
e. Curb (fig. 30). The curb is a 6- by 6-inch timber placed on 4-by 6-inch blocks and bolted to the deck. The 4- by 6-inch curb blocks are spaced to provide openings for draining surface water from
PROTECTION ANGLE
BEARING PLATE
TRACTION CLIP
the floor of the bridge. Curb bolts (fig. 6) are provided for fastening the curb to the timber deck.
LOCK WASHER
CURB BOLT ASSEMBLY
ANCHOR BOLT
STRUCTURAL RIBBED BOLT, COUNTERSUNK HEAD ERECTION BOLT
FLOOR CLIP
Figure 6. Fasteners for the 30- and 60-foot bridges. These parts are the same for both bridges except for lengths of structural ribbed bolts and dimensions of floor clips.
Section II
60-FOOT I-BEAM BRIDGE
15. Main Girders and End Bearings
a. Parts.
Mark Description Weight (pounds)
G2R End outer girder section (including splice) _ _ 3, 075
G2L End outer girder section (including splice) 3, 075
G3 Center outer girder section 3, 491
G4 End inner girder sections (including splice) 3, 065
G5 Center inner girder section 3 495
BP1 Bearing plate 31
AB1 Anchor bolt 4 3
b. Girders. This bridge is built of four girders connected by steel diaphragms to form a rigid box-type structure (fig. 2 and sheet 6). Each outer girder is fabricated in three sections; two end sections, G2R and G2L, and a center section G3. Each inner girder is fabricated in three sections; two end sections G4 and a center section G5. The sections are connected by two field splices (fig. 9). The girder sections are fabricated from 33-inch 132-pound wide-flange I-beams. The over-all length of the completed girders is 61 feet 6 inches.
c. End Bearings. End bearings are the same as for the 30-foot I-beam bridge described in paragraph 12c.
d. Anchor Bolt (fig. 6). Girders are held in place on the sills or abutment seats by anchor bolts AB1, described in paragraph 12d.
16. Bracing, Splices, and Fasteners
a. Parts.
Mark Description Weight (pounds)
D3 Intermediate diaphragm 154 132 21. 6 18. 9 Included with girder. Variable
1)4 End diaphragm
T1 T2 Diagonal lateral bracing _
Diagonal lateral bracing _
Splices
Bolts and nuts
b. Diaphragms. Diaphragms placed between the girders at the ends of the bridge and at 10-foot intervals make the structure rigid and distribute wheel or track loads among the girders (see sheets 6 and 7). They also serve as lateral bracing.
(1) Intermediate diaphragms D3 consist of four 3^- by 2%- by %-inch angles connected by %-inch gusset plates to form a frame. The frame is bolted to stiffener angles shop-riveted to the girders. Figure 7 shows the fabricated diaphragm and figure 2 shows the diaphragm installed in the bridge.
(2) End diaphragms D4 consist of 18-inch 42.7-pound channels connected to the ends of the girders.
c. Diagonal Lateral Bracing (fig. 8). Diagonal lateral bracing, T1 and T2, consists of 1-inch round rods with turnbuckles. The rods pass through 3-inch holes in the web of the girders (fig. 2).
INTERMEDIATE DIAPHRAGM
END DIAPHRAGM
Figure 7. Intermediate and end diaphragms for the 60-foot bridge. Diaphragms stiffen the bi idge and distribute wheel and track loads. They are bolted to the girders at 10-foot intervals.
d. Splices (fig. 9). Girder sections are joined by field splices. The webs of the I-beams are spliced with a plate on each side of the webs. The lower flanges are spliced with a plate on the lower side. The upper flanges are spliced with a plate each side of the web on the under side of the flange. Two fill plates, % and %6 inch thick, respectively, are provided with each splice. One or both fill plates may be needed depending on the difference in depths of the two girder sections. The use of one fill plate is shown in figure 33.
e. Bolts and Nuts. Fasteners used in this bridge are similar to those for the 30-foot I-beam bridge. See paragraph 13 and sheets 4 and 5.
17. Floor System
The floor system for this bridge is the same as for the 30-foot I-beam bridge. See paragraph 14.
5
Figure 8. Bearing plate, traction clip, diagonal lateral bracing, and protection angle for the 60-foot bridge.
Section III
90-FOOT TRUSS BRIDGE
18. Main Trusses and End Bearings
a. Parts.
Mark Description Weight (pounds)
U1R End post, sloped 740
U1L End post, sloped 740
U2 End upper chord section 1, 227
U3 Center upper chord section 1, 655
LI R End lower chord section 1, 129
LIL End lower chord section 1, 129
L2R Center lower chord section 1, 589
L2L Center lower chord section 1, 466
L3R End lower chord section 1, 129
L3L End lower chord section 1, 129
Pl Web vertical 293
Mark Description Weight (pounds)
P2 Web vertical 297
P3 Web vertical 324
W1.. Web diagonal 202
W2 Web diagonal 283
W3 Web diagonal 172
W4 Web diagonal 69
W5 Web diagonal _ _ 67
BP2 . Bearing plate 43
AB1 Anchor bolt 4. 3
b. Main Trusses (fig. 10). The trusses are shipped knocked down and must be assembled in the field. The upper chord is fabricated in five parts—two end posts and three sections of upper chord. The lower chord is fabricated in four parts. Each web member is fabricated in one piece. Gusset plates are shop-riveted to the chord sections (see sheet 9).
UPPER FLANGE SPLICE PLATES
132-LB. BEAM
LOWER FLANGE SPLICE PLATE
Figure 9. Splice joining girder sections of the 60-foot bridge. The two splice plates on lower side of upper flange provide a level upper flange surface for support of laminated timber decking. Fill plates balance difference in depth of I-beam sections.
(1) End posts, U1R and U1L, and upper chord sections, U2 and U3, are built-up members consisting of two 8-inch 13.75-pound chan-
6
PROTECTION ANGLE
DIAGONAL LATERAL BRACING
BEARING PLATE
TRACTION CLIP '
UPPER CHORD
WEB VERTICALS
END POSTS
WEB DIAGONALS
LOWER CHORD
DIAGONAL BRACING
INTERMEDIATE FLOOR BEAM
Figure 10. The 90-foot bridge assembled except for flooring. Note the position of the main members in the bridge. Also see sheet No. 15.
OUTER STRINGER
INNER STRINGER
SOLE PLATE
BEARING PLATE
END FLOOR BEAM
CABIN PLATE
END PEDESTAL
nels, one 14- by %6-inch cover plate, and stay plates with single lacing bars (fig. 10).
(2) Lower chord sections, L1R and L1L, are built-up members consisting of two 6- by 4- by /(-inch angles, 8% inches back to back, connected by batten plates. Lower chord sections, L2R and L2L, are built-up members consisting of two 6- by 6- by %-inch angles, 8% inches back to back, connected by batten plates (fig. 10).
(3) Web verticals, Pl, P2, P3, are 8-inch 31-pound wide-flange Z-beam sections fastened to the upper and lower chords by gusset plates.
(4) Web diagonals, W1 and W2, are wide-flange Z-beam sections, 8-inch 17-pound and 8-inch 24-pound respectively. Web diagonals, W3, W4, W5, are built-up members consisting of two angles 3- by 2%- by h-inch held 8 inches back to back by batten plates.
c. End Bearings. End bearings consist of a sole plate and a bearing plate BP2 (fig. 11). The sole plate is riveted to the bottom of the end pedestal. It rests and slides on the bearing plate during expansion and contraction of the bridge. The bearing plate is anchored to the sill or abutment seat.
d. Anchor Bolt (fig. 12). The trusses are held in place on the abutment seats by anchor bolts AB2, 1 foot 6 inches long. They are imbedded in the sill or abutment seat and extend through close fitting holes in the bearing plate and through holes in the sole plate. The sole plate has slotted holes on the expansion end of the truss and round holes on the fixed end.
19. Bracing, Splices, and Fasteners
a. Parts.
Mark Description Weight (pounds)
El Diagonal lateral bracing 77
E2 Diagonal lateral bracing. _ 37
E3 Diagonal lateral bracing 46
Bolts and nuts Variable
b. Bracing. Lateral bracing, El, E2, E3, consists of 2%-by 3- by %-inch angles placed diagonally below the stringers in each panel.
They are bolted to gusset plates in the lower chords of the trusses at the panel points (see sheets 9 and 10).
c. Splices. Details of splices of chord sections and connections of members are shown on sheets 9 to 13.
d. Bolts and Nuts. (1) Two types of bolts and nuts are used in this bridge:
(a) Machine bolts % inch in diameter with heads and nuts 1%-inch square are used as erection bolts. They are used to draw parts together in a tight fit while structural ribbed bolts are being placed (fig- 12).
(6) Structural ribbed bolts % inch in diameter with button or countersunk heads and 1%-inch self-locking hexagonal nuts are used for all field connections (fig. 12). These bolts are described in paragraph 13.
(2) See sheets 1 and 13 for detailed information on bolting.
(3) Bevel washers (fig. 12) are provided for use under nuts bearing on sloping flanges of top chord and floor beams.
7
Figure 11. Protection angle, bearing plate, and guardrail for the 90-foot bridge. Note the curved surface of the guardrail. The vertical face of the guardrail angle is stiffened by plate diaphragms welded between the two legs. Figure 50 shows guardrail installed.
b. Floor Beams. Both end and intermediate floor beams, Bl and B2, are 21-inch 63-pound wide-flange I-beams. They are placed between the trusses at the panel points as shown in figure 10 (see sheets 10 and 11).
c. Stringers. Four lines of stringers are placed between the floor beams (fig. 10). Outer stringers S2 are 12-inch 25-pound wide-flange I-beam sections. Inner stringers Si are 10-inch 21-pound wide-flange I-beam sections (see sheets 10 and 11).
d. Flooring. The flooring is similar to that for the 30-foot I-beam bridge. See paragraph 146 and sheet 12.
e. Protection Angle (fig. 11). The protection angle A2 is a 5- by 3K- by %6-inch angle, 5 feet 10 inches long. It has holes for nailing to the timber floor.
/. Guardrail (fig. 11). This bridge has positive steel curbs 8 inches high which serve as guardrails. The guardrail sections are 10 feet long and are bolted end to end. They are also bolted to the deck with guardrail bolts (fig. 12). Bearing spools are provided to increase the bearing area of the bolts on the timber deck.
20. Floor System
a. Parts.
Mark
Description
Weight (pounds)
Bl
B2 SI. S2.
End floor beam_________________________,
Intermediate floor beam________________
Stringer_______________,_______________
Stringer_______________________________
Flooring_______________________________
Protection angle_______________________
Guardrail______________________________
1, 093 1, 146
242 278 Variable 52
241
O.G. WASHER LOCK WASHER
BEARING SP OQI
guardrail; bolt assembly
ANCHOR BOLT
* * /
ERECTION BOLT BEVEL WASHERS /FLOOR CLIP
I ** /
X-..
STRUCTURAL RIBBED BOLT
50d CEMENT-COATED NAILS
A2___
A3___
Figure 12. Fasteners for the 90-foot bridge. The bearing spool and O. G. washer increase the bearing area on the timber deck. The anchor bolt can be used in masonry, concrete, or timber. If used in timber it may have to be cut to proper length.
PART TWO
ERECTION
CHAPTER 4
RECONNAISSANCE AND PRELIMINARY PLANNING
21. Reconnaissance Instructions
A ground reconnaissance must be made before construction is started. Instructions to the reconnaissance officer should include the general location of the bridge, traffic requirements, particularly if two-way traffic is required, and time available for construction. For a general discussion of reconnaissance instructions see FM 5-6.
22. Reconnaissance Procedure
a. Preparations. Specific reconnaissance plans should be made before going into the field. This insures obtaining correct and necessary data and avoids wasting time on nonessentials. Preparations include:
(1) Assembly and brief study of all maps and photographs immediately available.
(2) Assembly of necessary surveying instruments, tools, weapons, and transportation. Picks, shovels, bars, mauls, and an earth auger should be included for prospecting and sounding foundations. If available, photographic equipment is desirable to take pictures of sites.
(3) Review of the characteristics of the bridges to assure their proper use in the final plan. See chapter 2 for a summary of data on these bridges.
b. Conduct of Reconnaissance. Reconnaissance methods in general are discussed in FM 5-6. Detailed instructions for bridge reconnaissance are given in FM 5-10 (1944). Because the bridges described in this manual are nontactical, they often replace existing tactical bridges over which traffic must be maintained until the new bridge is complete. However, they are not necessarily built immediately adjacent to the tactical bridges being replaced.
23. Factors Affecting Exact Location
a. General. The general area in which the bridge will be built is limited by the existing road net. The exact location of the center line of the bridge is selected after careful study and analysis of available sites within the area. The following factors and requirements must be considered.
b. Approach and Access Roads. Approach roads having an easy grade and a straight section for at least 150 feet from each end of the bridge are preferable. Their grade line must be above high-water level. Access roads connect the bridge with the main road net.
8
Consideration must be given to the materials and labor required for their construction.
c. Length of Bridge. An ideal site is one where the crossing can be made with a single span with simple abutments on firm banks. Where such a site cannot be found or other factors make its use impracticable, a single span with earth-fill or timber-trestle approaches or a multiple-span bridge with intermediate piers must be constructed.
d. Clearance. The bridge elevations necessary at various sites to allow passage of flood water, ice, debris, and river or canal traffic must be considered.
e. Foundations. The condition of the banks and the character and bearing power of the soil for abutments as well as stream-bed conditions for piers must be thoroughly explored. Table XIV gives the loads abutments and piers must carry. Abutment and pier requirements at each site are important factors and must be carefully compared before making the final selection. Where intermediate piers are required, the difficulties of construction and the possibility of damage by scour, debris, and ice must be considered.
/. Scheme of Erection. (1) These bridges may be erected by several methods not equally applicable to all site conditions. Each site should be analyzed to determine the most practicable method of erection, and all sites under consideration should be compared on this basis.
(2 ) Equipment requirements for the various erection schemes are listed in table VII. The equipment available may be the determining factor. Likewise, it is important to consider the hazards involved in each method in relation to the skill and experience of the troops who will do the work.
(3 ) Several reliable methods for rapid erection of these bridges are described in chapters 7, 8, 9, and 10. Often it will be necessary to modify them to suit local conditions and sometimes entirely different schemes may be more appropriate.
g. Work Area and Bivouac. The requirements for the work area shown in figure 13 and discussed in paragraph 25 should be considered in selecting the exact bridge location.
h. Materials. The reconnaissance should determine the sources and availability of materials that may be used in constructing the bridge. Important items are timber for abutments, piers, and floors; gravel, crushed rock, or salvaged steel landing mat for road surfacing; and masonry or large stone for riprap.
i. Protection and Concealment. If the bridge is a vital link in a main supply road, the possibilities afforded by each site for concealing and protecting the bridge against aerial attack must be analyzed.
24. Survey
The selected site is surveyed to establish the exact center line of the bridge and to obtain an accurate profile of the crossing along this center line. The survey is extended back from the banks far enough to include all required road construction. The plotted profile is the basis for the bridge plans submitted with the reconnaissance report (par. 25). For details of surveys see TM 5-235 and FM 5-10.
591148°—44—2
25. Plans, Estimates, and Schedule
a. General. Plans are gradually evolved as examination of a site proceeds. After all pertinent factors and possible plans have been analyzed, one plan is adopted. Sketch drawings are made showing enough detail so required quantities of work, materials, labor, equipment, and transportation can be estimated. The proposed work organization and time schedule are then prepared.
b. Work Quantities. Amounts of clearing, drainage, excavation, and other work are estimated from the plans or from field measurements.
c. Bills of Materials. (1) Materials required for each bridge are listed on sheets 1, 5, and 8. These include all structural steel parts for each bridge and the necessary bolts, nails, flooring, and fittings. They do not include material needed during construction such as gin poles, cribbing, rope, and drift bolts, or materials for abutments and piers. Separate estimates are made of these requirements from the sketch drawings.
(2) Where the standard design must be modified the bill of materials is changed accordingly. If the site requires a special abutment or pier it must be designed and the bill of material made up for it.
(3) Materials required for constructing the bridges by various methods are listed in table IX. Where erection methods other than these are used special bills of material must be made.
d. Troops. (1) The number of troops required to construct each bridge depends on such factors as equipment available, number of spans, abutments, amount of road construction, and weather conditions.
(2) The normal troop requirement for erecting a single span of each bridge is shown in table X. These data may be used as a basis for estimating troop requirements under varied conditions. To this must be added the labor needed for constructing approaches and doing other work not on the bridge itself.
e. Equipment. The equipment required depends on the method of erection, number of spans, and site conditions. Table VII is a list of equipment required for various methods of erection. Most of the items in the list are organic equipment with engineer units; some are class IV items normally available in depots. Table VIII is a list of special tools required for rapid field assembly of these bridges (figs. 20, 21, 23, and 24). Tools not contained in organic sets of the unit concerned may be drawn from depots. Other equipment needed for road construction, pile driving, excavation, and similar operations must be added to the equipment lists for steel erection.
f. Transportation. Transportation required to move bridge material to the site is given in table III.
g. Work Organization. Careful planning and layout of the work area facilitates construction and eliminates unnecessary work and moving of material. An example of a work-area plan is shown in figure 13. In planning the layout provision must be made for—
(1) Storage of materials so they can be processed, assembled or fabricated, and moved into place in the bridge with minimum interference. Separate storage of materials by classes is desirable.
(2) An assembly area where steel can be assembled preparatory to launching into place on the abutments.
(3) Roads with a drive-through arrangement or ample turn-around equipment and vehicles, especially trucks and trailers, can move in and out without backing up or blocking other activities.
(4) Storage and care of small tools and equipment and dispersion of heavy equipment when not in use.
h. Scheduling. To estimate the time required to build any bridge it is advisable to work out a schedule of operations. Specimen work schedules are shown in tables XI, XII, and XIII. Such a work schedule also is useful during actual construction as an aid in job supervision and control.
26. Reconnaissance Report
a. General. The reconnaissance report summarizes the data obtained and transmits the recommended plan of construction. The report should be concise but must contain all essential facts. The outline below will serve as a check list during the reconnaissance and as a guide in making the report. It should be modified to suit local conditions.
b. Outline of Bridge-Site Reconnaissance Report. (1) Reference and reconnaissance instructions number.
(2) Purpose of reconnaissance.
(3) Date, time, and period of reconnaissance.
(4) Date and time of report.
(5) Factors affecting the problem:
(a) Situation-existing facilities for crossing such as bridge, ferry, ford, or bypass.
(6) Terrain.
(c) Available labor, equipment, materials, and transportation.
(d) Time available.
(c) Technical considerations—access roads and approaches, length of bridge, clearance, foundations, stream bed, stream characteristics, erection schemes.
(/) Concealment and protection.
(6) Proposed plan:
(a) General description of site including vicinity sketch and area sketches showing locations of new bridge, existing routes of communications, local materials, work area, and bivouac.
(6) Plan, elevation, and cross sections of proposed bridge and supports with explanatory notes covering erection scheme and special features.
(c) Bills of materials and summary of labor, equipment, and transportation required.
(dj Time schedule.
(7) Recommendation.
(8) Signature, rank, and organization.
(9) Annexes—maps, photographs, sketches.
27. Ordering
a. Structural Steel. The structural steel for each bridge may be ordered as one unit complete or by individual items. The stock numbers are given for the complete unit in the bills of materials on sheets 1, 5, and 8. It should be noted that the unit complete does not include lumber for floor.
9
MEMBERS OF TRUSSES-FAR SIDE
BEAMS AND STRINGERS
ABUTMENTS
MEMBERS OF TRUSSES-CENTER
CONSTRUCTION AREA
MEMBERS OF TRUSSES—NEAR SIDE
MPMMMBi
EXISTING ROAD
ACCESS ROAD
n ABUT ’ MAT'L
Figure 13. Typical layout of work area for the 90-foot bridge. A similar scheme may be followed for the 30- and 60-foot bridges. Peculiarities of site may require some changes. Provision is made for entrance and exit of traffic and the cleared area is for assembly and launching of trusses. Material is placed near where it will be used but is distributed to prevent congesting the work area. The photograph shows the storage of material for a 90-foot bridge.
EXISTING BRIDGE
r"~
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r
’ i
•
ABUT MATT
EXIT ROAD
FLOORING AND GUARDRAIL
CONSTR MAT'L
I TOOLS |
REA
aw
NEW BRIDGE SITE
CONSTR
AREA
FLOOR BEAMS STRINGERS.
BRACING, CONNECTIONS
FAR-SIDE
MEMBERS
CENTER MEMBERS
EQUIPMENT AND MOTOR PARK
b. Lumber. Lumber for all purposes must be requisitioned separately.
c. Equipment. Necessary construction equipment not organic with the unit building the bridge is drawn from engineer depots.
d. Other Material. If not locally available all other materials are requisitioned from depots.
10
CHAPTER 5
ORGANIZATION OF WORK
28. Preliminary
a. Pioneer Work. Troops charged with the construction move up with pioneer tools and dozers to establish security and build pioneer access roads, clear the site, and provide drainage.
b. Access Roads. Existing roads may have to be improved or new roads constructed to provide access to the site. High priority must be given to this work to permit early delivery of equipment and supplies.
c. Preparation of Site. The work area should be prepared in accordance with plans in the approved reconnaissance report (par. 26). Preparation of site includes:
(1 ) Clearing, leveling, and draining areas for storage of materials, assembly of steel, turn-arounds, tools, and equipment.
(2 ) Providing shelter for tools and supplies.
(3 ) Providing dunnage for storage of materials.
29. Assembly of Equipment
a. General. Tools and equipment needed for construction should be assembled and prepared for use before they are required. Priority should be given to tools and equipment needed in the early stages of construction.
b. Storage. Provision should be made for storing tools under shelter at the site. Vigilant supervision is necessary to make certain tools and equipment are returned to their storage place when not in use.
c. Maintenance. Daily inspection, cleaning, lubrication, and repair are essential if tools and equipment are to be kept in good working order at all times. It is particularly important to check ropes, slings, blocks, winches, brakes, and other equipment carrying heavy loads. This prevents serious accidents and delays.
30. Assembly of Material
a. General. All material required for construction of abutments and piers, for erection of steel, and for the bridges is assembled at the site without delay. Priority is given to securing material needed in the early stages. Assembly of materials is coordinated with the time schedule (par. 25).
b. Blocking for Shipment. Care must be taken in transporting and assembling bridge steel to prevent bending, buckling, or other damage. Vulnerable parts like gusset plates, pedestals, splices, bracing, and diaphragms are protected during shipment from depots by timber bracing and blocking (fig. 14).
c. Storage. Material delivered to the site should be immediately sorted and stored in its proper area (fig. 13). Timber dunnage is used to keep steel parts off the ground. Where steel is stacked dunnage is used between members to facilitate handling (fig. 15). Small parts like bolts, nuts and washers, nails, and floor clips should be stored under cover to protect them from the weather.
31. Transportation
a. Truck-Trailer. All of the bridges can be transported by 8-ton or 16-ton full flat-bed trailers (fig. 16). The number of loads required for each bridge is shown in table III. Other trailers may be used for transportation of material (fig. 17). Trailers should be loaded or unloaded with a truck crane (fig. 15). However, many parts can be unloaded by hand (fig. 17).
b. Rail. Units constructing these bridges ordinarily are not concerned with rail transportation. However, they may be responsible for unloading the bridges at rail sidings. All of the steel members can be carried in single standard-gauge commercial railway cars but some are too long for U. S. standard military railway cars. Where military cars are used the long members are placed so the weight rests on one car, called the load car, and the overhang extends over an adjacent car, called the idler car. It may be necessary to support the overhang in a cradle on the idler car. The number of military and commercial cars required for each bridge is given in table III.
32. Construction Surveys
a. General. (1) Construction surveys with transit, level, and tape are made to stake out work on the ground and to establish accurately the positions and elevations of bearing plates. Surveys are required to fix the locations of center-line of bridge, center line of abutments, elevation of footings and sills, center line of bearing plates, and position of anchor bolts.
(2) Bridge surveys are discussed in FM 5-10 (1944). Instructions on the use of instruments in construction surveys are given in TM 5-235.
(3) The following paragraphs describe construction surveys for a single span with a simple timber abutment. The same methods apply generally to bridges on other abutments and to multiple-span bridges with intermediate piers (fig. 18).
b. Location of Center Line of Bridge and Abutments (fig. 18®). The center line of the bridge is located by stake set with a transit and tape. The position of the center of the end bearings is accurately marked on the bridge center line. Then the center line of each sill is established by turning a 90-degree angle from the bridge center line. Reference stakes for all center lines and a bench mark are set outside the construction area where they will not be disturbed.
c. Elevation of Abutment Footings. The elevation of the bottom of the footings depends on the abutment design. Once the elevation for the top of the bridge floor is established, the elevations ol footings and bearing plates is obtained by subtracting the dimensions of intervening material as illustrated in figure 18®.
d. Center Line of Bearing Plates. When the excavation for
footings is complete and footing and sill installed, the center line of the bearing plates is laid out on the sill. The location of each bearing plate is obtained by measuring the distances d and d' from the center line of the bridge as shown in figure 18®.
e. Position of Anchor Bolts. Anchor bolts are located by measuring the distance a from the center line of the bearing plate and the distance b from the center line of abutment sill as shown in figure 18®. An alternate method is to use the bearing plate as a template for locating the bolts.
/. Accuracy. Accurate measurements are extremely important to establish correctly the positions of the anchor bolts. Check measurements should be made after the anchor bolts are installed and before launching operations are started.
11
12
Figure Ij. Timber blocking bolted to members to protect them during shipment.
— —• .'Maw* - '-
© Placing anchor bolts and bearing plates for the 30-foot bridge. The anchor-bolt nut and wood block protect the bolt while it is being driven. Anchor bolts are cut off to fit the timber sill.
@ Construction of abutment for the 60-foot bridge. Footers are 3- by 12-inch plank and the sill is a 6- by 12-inch timber. The end dam consists of 12- by 12-inch posts capped with 6- by 12-inch timber and surfaced with 3- by 12-inch plank.
Figure 19. Simple types of timber abutments built for these bridges.
@ Abutment for trial erection of the 90-foot bridge. A spread footing of 3- by 12-inch plank is placed under each truss end bearing point.
end, which is the expansion end, the nuts are run down on the anchor bolts but not tightened.
(2) The fixed end of the 90-foot truss has round holes in the sole plate through which the anchor bolts project. The expansion end of the bridge has slotted holes. Anchor-bolt nuts are tightened on the fixed end; they are run down but not tightened on the expansion end.
35. Special Erection Tools
a. Driftpins (fig. 20). Steel driftpins with tapered ends are used to align holes in members to be connected.
b. Shackles (fig. 21). Temporary connections to steel members can be made by using a shackle as shown in figure 22. Shackles are also needed to make connections with steel blocks.
c. Ratchet Chain Hoist (fig. 21). The ratchet chain hoist is useful in drawing members into alignment (fig. 22) and in tightening snub lines.
d. Spud Wrench (fig. 20). The spud wrench is a useful combination tool for aligning holes to receive driftpins and for tightening nuts.
e. Slings. Wire-rope slings are needed for handling heavy members and for launching girders and trusses. See figure 23 and TM 5-225.
J. Connecting Bar (fig. 20). The 3-foot connecting bar is useful in alining members and in applying leverage when assembling steel.
g. Pinch Bar (fig. 21). Five-foot pinch bars are needed for guiding members into position.and applying leverage during assembly of steel and during launching.
36. Assembling Steel Members (fig. 33)
a. Preliminary Bolting. Parts to be connected are brought together in position for bolting. A drift pin driven through every second or third hole aligns the parts and holds them together while erection bolts are placed. Erection bolts are put in every second or third hole and nuts are tightened until the metal parts are drawn tightly together. If plates do not bear tightly together hammer on plates around the bolt head and draw up on the nut at the same time. The purpose oh erection bolts is to draw the parts to a tight fit and hold them until final bolting is completed.
b. Final Bolting. Final bolting is done with structural ribbed bolts in the following order:
(1) To insure good alignment of bolt holes a drift pin is driven through each hole before the structural ribbed bolt is driven.
g 3-POUNO HAMMER CRESCENT WRENCH
fll RATCHET WRENCH
I DRIFT PIN
8-POUND SLEDGE
SPUD WRENCH
3-FOOT CONNECTING BAR
Figure 20. Erection tools for assembling steel members of all three bridges. The offset of the spud wrench permits access to tight places and the tapered end of the handle is used in aligning holes in members to be connected. A ratchet wrench extension is needed to tighten the bolts in the upper chord splice of the 90-foot bridge.
15
15-TON JACK 25-TON JACK
Figure 21. Erection equipment for handling heavy steel members of these bridges. Precautions must be taken when raising or lowering, heavy loads to prevent jacks from, kicking out.
b. Wire Rope. Wire rope should consist of 6 strands of 19 wires each and should be made of plow steel. The following sizes should be used:
(1) 30-feot bridge.
1 part inch.
(2) 60-feot bridge.
Side guys for gin pole—1 part % inch.
Back guys for gin pole—2 parts % inch.
Tackle for one girder—2 parts % inch.
Tackle for two girders—4 parts % inch.
(3) 90-feot bridge.
Guys for gin pole—same as for 60-foot bridge.
Tackle for single truss—2 parts % inch.
c. Steel Blocks (fig. 24). Steel blocks should be used for all rigging where wire rope is required. The strength of the sheave pin and the hook (or shackle) must be sufficient to withstand the loads that will be placed on the block. Size and kind of blocks for each method of erection is given in table VII. Steel blocks equipped for shackle connection are preferable to blocks with hooks.
d. Adjustment of Gin Pole. Gin poles placed on the center-line of the bridge behind the abutment can be used for all work on one bridge. The pole is tilted as required, the rope tackle shown in figure 25 being used to adjust the guy lines. Figure 25 also shows details of rigging at the top of the gin pole.
e. Sling for Climbing Gin Pole (fig. 25). A bowline on a bight as a rope sling is useful in hoisting a rigger up the gin pole to check connections and make changes and adjustments in the rigging.
38. Precautions in Handling Structural Steel
Care must be exercised in transporting, storing, assembling, and erecting structural steel members of these bridges. If members are bent, kinked, or otherwise damaged, the steel may be stressed beyond its elastic limit and fail under critical loads. In addition such damage makes it difficult to connect members. Wood blocks should be placed between slings and members where there is danger of bending flanges of beams or channels.
(2) Structural ribbed bolts are placed first in bolt holes that are not filled with the drift pins or erection bolts described in a above.
(3) Structural ribbed bolts are driven with a 6- or 8-pound sledge or a pneumatic hammer. After a bolt is well seated the self-locking nut is run on and tightened to a snug fit.
(4) When all open holes have been filled the remaining drift pins are removed and replaced with structural ribbed bolts; then erection bolts are removed one or two at a time and replaced with structural ribbed bolts.
c. Precautions. (1) An efficient connection is one in which the steel members fit tightly together. To obtain such a fit metal parts must be drawn tightly together with erection bolts and held until structural ribbed bolts have been driven and locked.
(2) Structural ribbed bolts having correct length and diameter must
be used. They should not be removed and redriven. Sheets 1, 5, and 13 contain information on bolt diameter, length, and position in the bridges.
(3) Structural ribbed bolts must not be used for drawing parts together. Threads on the bolts will strip if the nuts are tightened beyond a snug fit.
(4) Structural ribbed bolts are driven whichever direction is easier. If this factor is not decisive always drive towards the heavier member being connected.
37. Rigging
a. General. For general information on rigging see TM 5-225. Specific information for these bridges is given in the following paragraphs.
39. Safety Precautions
The -following safety precautions are emphasized:
a. Make sure all connections are secure. This applies to slings, shoring, snubbing, temporary bolting, and wire-rope clips.
b. Make sure equipment is not overloaded.
c. Make sure girders and trusses are adequately shored and tied to prevent their falling when in the upright position.
d. Keep personnel out of line of all cable under stress and away from the underneath side of steel being placed.
e. Make sure winches have positive brakes and efficient clutches so the operator has complete control of loads at all times. This is particularly important in slacking off to lower members into position.
/. Guy lines must be rigged and anchored to take the loads placed on them. The back guy and anchorage takes most of the load when launching by the methods described in chapters 7, 8, 9, and 10. When
16
1-INCH SHACKLE
V/2-INCH SHACKLE
RATCHET CHAIN HOIST
5-FOOT PINCH BAR
Figure 22. Using the ratchet chain hoist to draw members of the truss together. The connection to the truss member is made with a l-inch shackle and an erection bolt.
Figure 23. Wire-rove slings used for attaching tackle and lines to heavy steel members
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Figure 24- Steel blocks required for launching the bridges by several launching methods.
591148°—44---3
17
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® Detail of rigging at top of gin pole.
@ Sling made with manila rope for hoisting a rigger up the gin pole. Rigging is attached to the gin pole before it is raised but it is sometimes necessary to climb the pole to check connections and make adjustments or changes.
© Tackle of 1-inch manila rope and the double and single manila-rope blocks shown in figure 2^. It is used for adjusting guy lines when necessary to tilt the gin pole.
Figure 25. Gin-pole rigging details.
18
rigging the gin pole caution must be taken to insure the back guy or anchorage will not fail.
g. Before launching girders or trusses, place load on equipment, release, and check all connections and rigging.
h. Before launching girders or trusses, have operator lift and lower the unit several times to “get the feel” of the operation.
i. Make sure the operators of the winches and crane work together and do not overload the equipment. Overloading will be avoided if both ends of the unit being launched are kept level. It is better to have the far end low than high during launching.
j. If girders or trusses are to be lowered to the abutments with jacks and cribbing, precautions must be taken to prevent jacks from “kicking out.” This can be prevented by lowering the unit short distances at a time. Do not attempt to lower both ends at once.
CHAPTER 7
ERECTION OF 30-FOOT BRIDGE
40. General
a. Drawings. General and detailed drawings of this bridge are given on sheets 1 to 4 inclusive.
b. Equipment. Because of their weight, the girders must be unloaded, spotted for assembly, and launched by mechanical means such as cranes and gin poles. Main items of equipment required for each of the several methods of launching are listed in table VII.
Figure 26. Placing girders for the 30-foot bridge with a %-cubic-yard truck crane. The outrigger prevents crane from tipping. Hand lines guide the girder into place on the bearing plates.
19
il
(T) First phase: Diaphragms are bolted to the girders to connect them in pairs. A cable from the tractor winch is attached and the girders are pulled across the gap.
@ Second phase: Plank skids guide the girders into position over the bearing plates.
® Third phase: Girders on blocks in position over the bearing plate.
@ Fourth phase: The timber provides enough leverage to lift the end of the girders so blocking can be removed and girders lowered to bearing plates.
© Fifth phase: Placing diaphragms between the two sets of girders on the abutments. Note the timber support placed on the lower flanges of the girders.
Figure 27. Erection of the 30-foot bridge by skidding pairs of girders into place with
a tractor.
20
Figure 28. Skidding a girder into place for the 30-foot bridge using a tractor winch for power. Note use of skids. The girder is rotated to the vertical position and placed on the bearing plate by hand. Note the position in which the traction clips are shipped. They must be changed before laying flooring.
The weights to be handled are as follows:
Single girder__________________________ 2,600 pounds.
Two girders connected__________________ 5,700 pounds.
c. Assignment of Tasks. Table XI may be used in sotting up a schedule of work and work parties. Construction may be speeded by:
(1) Transporting and unloading material, constructing abutments, and assembling first units during the first stage.
(2) Bolting first unit while second unit is being assembled, at same time placing bolts and bearing plates on the sill.
(3) Launching first unit while bolting of the second unit is being completed,
Figure 29. Bolting diaphragms to girders with structural ribbed bolts. Note use of ratchet wrench.
(4) Having one party complete bolting girders which have been placed while a second party begins to lay the floor.
(5) Having other work parties start placing guardrails, wearing surface, and protection angles, while the floor is being laid.
41. Assembly of steel
If beams are placed on the abutments one at a time, no assembly before launching is required since the beams are made in one piece. Traction clips, shipped bolted to beams, are removed and bolted in the correct position. Beams may be launched in pairs in which case assembly consists of bolting end and intermediate diaphragms to the two beams.
42. Launching
a. Truck Crane (see method A, table VII). A truck or tractor crane with a 2,600-pound capacity at a 20-foot radius can pick up the beams and place them on the abutments (fig. 26). Hand lines on the ends of the beam aid in guiding it into position. Two men with pinch bars assist in guiding the beam into its final position over the anchor bolts.
b. Skidding (method B, table VII). Where conditions permit, a simple method of launching is to connect the I-beam in pairs and drag the pair across the gap. Figure 27 shows a tractor placing a pair of beams by this method. Skids are used to guide the beams to a position over the anchor bolts from which they are lowered by hand or jacking. Single beams can be placed by the same method (fig. 28).
21
@ Placing laminated timber deck. Floor clips are placed so they bear solidly against the edge and under side of the beam flange.
@ Laying plank wearing surface.
Figure 30. Installing timber floor and curb on the 30-foot bridge.
@ Installing timber curb. The bearing area of the curb bol ton the timber curb and deck is increased by using 0. G. washers. Curb blocks provide opening for drainage.
® Partly decked bridge showing the curb, wearing surface, and protection angle in place. Approach construction not complete.
22
c. Alternate Methods. Any of the methods given in chapter 8 for launching the 60-foot bridge may be used for launching this bridge if conditions warrant the additional work involved.
43. Completion of Bridge
a. Setting Girders. Girders are set with anchor bolts located in the center of the slotted expansion holes. When girders are in place on the bearing plates, they are connected by bolting the diaphragms to the stiffener angles (fig. 29).
b. Installation of Floor (fig. 30). (1) Traction clips are bolted with structural ribbed bolts with countersunk heads.
(2) Two 2- by 6-inch planks are set on edge so they bear against the traction clips. Nails are driven through the planks toward the abutment and clinched. The third plank is placed against the second and nailed. See nailing scheme on sheet No. 4 for spacing of nails.
(3) Floor clips are fastened to the third plank and to each eighth plank thereafter. See scheme for floor clips on sheet No. 4. Make certain that clip bears solidly against under side and edge of girder flange.
(4) The remaining deck planks are placed and nailed. It may be necessary to notch the last plank so it will bear properly against the traction clip.
c. Installation of Curb (fig. 30®). Curb blocks are set at proper intervals and toenailed in place. Curbs are placed on top of blocks and held in place by toenailing. Holes are bored through curb, blocks, and deck. Bolts are driven, washers placed, and nuts tightened.
d. Wearing Surface and Protection Angles. Wearing-surface planking is spiked to the deck (fig. 30®). Protection angles are fastened to wearing surface at ends of bridge (fig. 30®).
44. Removal of Bridge
The procedure for removing this bridge is the reverse of that by which it was assembled and launched.
® Position of girder sections for assembling and launching a single girder.
Figure 31. Layout of girder sections for assembly of 60-foot bridge.
CHAPTER 8
ERECTION OF 60-FOOT BRIDGE
45. General
a. Drawings. General and detailed drawings of this bridge are given on sheets 4 to 7 inclusive.
b. Equipment. Mechanical equipment such as gin poles or cranes is required for handling members of this bridge. See table VII for main items of equipment required for each of the several methods of launching. The weights to be handled are:
Heaviest girder section______________ 3,500 pounds.
One girder complete___________________ 10,000 pounds.
Two girders connected_________________ 22,000 pounds.
Position of girder sections for assembling and launching a pair of girders.
23
c. Assignment of Tasks. Table XII may be used in setting up a work schedule and work parties. The scheme given in paragraph 40c for assigning tasks for the 30-foot bridge applies to this bridge as well.
46. Assembly of Girder
a. Single Girder. If girders are to be launched as single units, sections are placed as shown in figure 31® and bolted together at the splices.
b. Double Girder. If girders are to be launched in pairs, sections are placed as shown in figure 31®, the four splices completed, and the diaphragms connected (fig. 32).
c. Position of Sections. All girders should be assembled with the holes for lateral rods toward the top. Outside girders are placed so the angle plate anchor for lateral tie rods is on the outside.
d. Splicing Girders (fig. 33). (1) The sections of the girder to be spliced should be set on blocks at working height and adjusted to proper grade and alignment relative to each other.
(2 ) Web splice plates are bolted first (fig. 33®).
(3 ) Upper flange splice plates are placed and bolted next (fig. 33®).
(4 ) Before bolting the lower flange plates (fig. 33®), the girder is placed on its side or is raised high enough to permit driving structural ribbed bolts with the pneumatic hammer. Before bolting, the lower flange should be checked to see if a fill plate is required. Because of slight variations in depth of girder sections, it may be necessary to use one or both of the fill plates furnished with the splice material (figs. 9 and 33®). The holes in the webs are located so the top flanges on both sides of the splice are flush when holes are aligned. If no fill plate is required for the bottom flange splice, some of the structural ribbed bolts will be too long. If they are, cut washers provided should be used under the nuts.
47. Launching.
a. General. Girders for this bridge may be launched singly or in pairs. The single-girder method is preferred because of the additional weight involved when launching two at one time. However, if equipment is capable of handling the weight, the two-girder method is quicker and girders are easier to launch because they are less likely to tip.
b. Gin Pole-Crane Method (method C, table VII). A gin pole is erected on solid footing 5 feet behind the center of the far-side abutment. Wire-rope guys with steel blocks are used; a rope tackle (fig. 25) is rigged to each guy line for adjusting the angle of the pole. A line is run from a winch on the near bank to the pole and back to the far end of the girder. The tackle required is determined by the number of girders to be launched, the size of wire rope, and the equipment available (see par. 37, ch. 6). Wire-rope slings are used to fasten the tackle to the girders. A tractor- or truck-mounted crane is snubbed to the near end of the girder as a brake. A line from the crane boom is attached to the near end of the girder to steady it. Power from the winch pulls the girder across the gap. Figure 34 shows a girder being launched by this method. When the near end approaches the abutment, the crane picks it up and lowers it onto the sill. Two girders connected by diaphragms can be launched the same way.
24
c. Gin Pole-Tractor Method (method D, table VII). A gin pole is rigged as in method C above and tackle from the pole is attached to the girder. The lead line is powered by a winch on the near bank. A tractor with dozer is snubbed to the girder as a brake. When the girder is in position for lowering to the sill, a sling attaches the girder to the blade of the dozer. The gin-pole tackle lowers the far end and the dozer blade lowers the near end (fig. 35). If two girders are launched at one time they are lowered with jacks or a crane (fig. 36).
d. Alternate Methods. The methods discussed in chapter 9 for launching the 90-foot truss are applicable to this bridge if conditions warrant the additional work involved.
48. Completion of Bridge
a. Setting Girders. Girders should be placed so anchor bolts are in the center of the slotted expansion holes. After girders are in place on bearing plates and nuts on anchor bolts are properly tightened, diaphragms are bolted to girders (fig. 37).
b. Lateral Bracing. When diaphragms are in place the lateral rods are placed (fig. 38). The turnbuckles should be tightened enough to remove the slack and stress the rods slightly but care should be taken to avoid setting up considerable stress in the rods. If the center of the bridge is not in true alignment with the ends, proper adjustment of the laterals will bring the bridge in line.
c. Installation of Floor and Curb. Instructions for installation of flooring, curb, wearing surface, and protection angle are identical to those given for the 30-foot bridge described in paragraph 436.
49. Removal of Bridge
The bridge is removed in the reverse manner to that in which it was assembled and launched. Girders are removed singly or in pairs by one of the methods given for launching. If the bridge is to be moved to a new site and erected again, single assembled girders can be transported on a trailer without disconnecting the splices.
Figure 32. Bolting diaphragms preparatory to launching a pair of girders of the 60-foot bridge.
Q Assembling girder sections preparatory to splicing. One section being moved with crane. Timber blocks and wedges adjust sections to correct fit.
@ Support and shoring for girder. The girder is placed on the ground before launching.
® Align bolt holes with driftpins before bolting. Machine bolts are used during @ erection to hold the members tightly together until structural ribbed bolts are placed. Note the spud wrench and use of the pneumatic hammer for driving @ the structural ribbed bolts.
Figure 33. Splicing girder sections preparatory to launching girders of the 60-foot bridge.
Bolting upper flange splice plates. Driftpins align holes and erection bolts are placed and tightened; then structural ribbed bolts are placed.
Driving structural ribbed bolts in lower flange splice. Note the clearance required under the girder for the pneumatic hammer. If sledges are used for driving bolts the girder is laid on its side. Note use of fill plate.
591148°—44-
■4
25
® The girder on the approach preparatory to launching. A line is run from the truck winch to the gin pole (not shown) and back to the jar end of the girder. The near end of the girder is supported by the truck crane.
® Launching the girder. The gin-pole line pulls the girder across the gap. The crane is snubbed to the girder and acts as a brake. The vertical lift given by the crane line helps keep the girder from tipping.
® Placing the girder on the abutments. The crane lowers the near end and the ginpole line lowers the far end. Pinch bars are used io guide the beam into position on the anchor bolts.
Figure 34- Launching a girder for the 60-foot bridge with a gin pole and %-cubic-yard truck crane.
26
® Launching the girder. A line from the gin pole supports and pulls the girder across the gap. The tractor is used as a brake to control the girder.
:W'<
@ Last phase of launching using the dozer blade on a tractor to lower the end oj the girder, A pinch bar is used to skid the girder to the bearing plate.
■ ' ■
s.„
Figure 35. Launching a girder for the 60-foot bridge with a gin pole and tractor.
@ Placing the far end of the girder on the abutment.
27
Figure 36. Launching a pair of girders for the 60-foot bridge with gin pole and tractor. The tractor acts as a brake to prevent the girders from sliding too rapidly. The girders are placed on the bearing plate with a crane or if that is not available they are lowered with jacks. Note the method of connecting the tackle to the girders (see inserts).
Figure 37. Placing intermediate diaphragms after girders have been placed. Planks are placed on the lower flanges of the girders to support the men.
Figure 38. Installing diagonal lateral bracing. Tie rods are tightened only enough to bring girders into proper alignment. See figure 2 for completed structural steel work.
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CHAPTER 9
ERECTION OF 90-FOOT BRIDGE
Section I.
GENERAL
50. Methods of Erection
a. General. Several practical methods of erecting this bridge have been developed and are described in this chapter. In general the methods are divided into two classes:
(1) Erection by assembling single trusses on the approach, launching trusses one at a time, and building the floor system over the gap.
(2) Erection by assembling the entire bridge on the approach and launching it into place. Where site conditions permit the bridge can be assembled on a raft and floated into place.
b. Factors to be Considered. Single-truss erection is recommended. It is more economical of labor, material, and time. However, peculiarities of site and lack of equipment may warrant the other method.
c. Equipment. Mechanical equipment is required for the erection of this bridge. Table VII lists the principal items of equipment required for each method of erection. Weights to be handled are:
Heaviest truss member__________________ 1,650 pounds.
Heaviest floor beam____________________ 1,150 pounds.
Single truss__________________________ 15,000 pounds.
Total structural steel________________ 57,000 pounds.
51. Erection
a. Drawings. General and detailed drawings of this bridge are given on sheets 8 to 13 inclusive.
b. Assignment of Tasks. See table XIII as a guide in setting up a work schedule. Erection can be speeded by working on several tasks at one time. For example, if the bridge is to be built by launching single trusses, work may be done in the following stages:
(1) First Stage. Transporting and unloading material, constructing abutments, assembling first truss, rigging gin pole.
(2) Second Stage. Launching first truss; assembling and launching second truss.
(3) Third Stage. Installing floor beams and stringers; beginning construction of floor.
(4) Fourth Stage. Finishing floor, placing guardrail; removing gin pole, cleaning up area.
c. Assembly of Steel. Assembly of steel members depends on the method of erection used. A procedure for each method is de-
Figure 39. Connecting members U2 and P2. Erection bolts hold the fill plates while member U2 is placed. The connecting bar guides the member into position.
scribed in sections II and III. Some aids to assembling steel members are listed below:
(1) A ratchet chain hoist and shackle may be used in drawing members together where the fit is close (fig. 22).
(2) The 6- by %- by 8-inch fill plates at joint U2 make it difficult to join members P2 and U2 (fig. 39). This difficulty is overcome by tack welding the fill plates to member U2.
(3) Shore and tie truss on one side only to keep the other side clear for operation of equipment.
Section II.
ERECTION BY LAUNCHING SINGLE TRUSSES
52. Assembly of Truss
a. Equipment. A small crane or derrick greatly facilitates assembly of trusses. However, assembly can be done with a small gin pole used to lift members into place.
b. Preliminary Preparations. A plank is bolted to the bottom of the lower chord to form a rail for the truss to slide on in launching. Figure 40® shows a method of attaching the plank. A skid is built on the bottom of the near-side pedestal to aid in sliding the truss on the approach (fig. 40®). Cabin plates are removed from end pedestals. Camber blocks are prepared (see sheet 14 for camber diagram).
c. Order of Placing Truss Members (See sheet 14). (1) Sections of the lower chord are spliced and placed on the camber blocks (fig. 41 ®). The truss should be assembled with expansion end toward far bank.
(2) Far-side web vertical Pl, web diagonal Wl, and end post U1R are placed.
(3) Far-side web verticals, P2 and P3, and right web diagonals, Wl and W2, are placed.
(4) Upper chord U2 is placed (fig. 41®).
(5) Members listed above are placed on the near-side of the truss (fig. 41®).
(6) Two center web verticals P2; center web diagonals, W3, W4, and W5; and upper chord center section U3 are placed (fig. 41®).
Note. Member U3 must be placed last because of arrangement of gusset plates on other upper chord members.
(7) Place cabin plates on end pedestals. Do not bolt until end floor beams have been bolted to trusses.
53. Launching Truss
a. General. Several methods of launching single trusses have been developed. The method with a gin pole and crane is recommended if equipment is available and site conditions permit. Other methods are described to permit selection of a method best suited to conditions on a particular job.
29
® Plank bolted to lower chord of truss to act as a launching rail. Note method of bolting on both sides of the batten plate. See also figure 43.
® Timber skid built under near end of truss to support it during launching. Figure 40. Preparatiorts for launching truss for 90-foot bridge.
b. Gin Pole and Crane (method E, table VII and fig. 42). (1) Preparations. A gin pole is erected on solid footing 5 feet behind the center of the far-side abutment. Wire-rope guys are equipped with rope tackle (fig. 25) to facilitate adjustment of the angle of the pole. Tackle consists of wire rope and steel blocks (see chapter 6). A line is run from the winch to the block on the pole, back to the block attached to the top chord of the truss, then to the top of the pole. Tackle is attached at joint U1 on the far end of the truss. A tractor- or truck-mounted crane is snubbed to the near end of the truss to act as a brake (fig. 43). The crane boom line is attached at near-end joint Ul. A temporary timber frame is built at the near abutment to aid in keeping the truss upright. It is removed when the truss is near the abutments.
(2) Launching. Power is applied by the winch and the truss is pulled toward the far-side abutment. The crane assists in sliding the truss forward by applying tension on the boom line and also controls forward movement by the snub line. The boom line also assists in keeping the truss upright because of the vertical pull exerted. The crane moves forward with the truss, keeping the snub line taut to prevent too rapid movement. When the truss is near the final position, a second snub line is attached at joint L2 and controlled by a winch on a truck or tractor. The snub line is released from the crane and the truss is swung into position over the abutments by lifting the far end with the gin pole and the near end with the crane. The skid is removed from the pedestal and the near (fixed) end of the truss is lowered to the bearing plate. The far (expansion) end is placed last. Figure 44 shows the truss being launched by this method. Caution. The %-cubic-yard truck crane, if used, will be near tipping load at the radius required for lowering the truss to the abutment sill. The approach must be level and firm. It may be necessary to anchor the crane chassis. Counterweights may be added to the crane chassis or a tractor may be snubbed to it.
c. Gin Pole Without Crane (method F, table VII). This method is similar to the one described above except that a crane is not required. The truss is pulled across in the same manner but without the aid of the crane. There is some danger of the truss tipping sideways with this method since there is no vertical lift on the near end of the truss. Precautions are taken to avoid this by constructing an A-frame skid to support and brace the truss while it is being launched (fig. 45). Guy lines may be used for the same purpose (fig. 46). A brake should be provided by a tractor or truck winch line attached to the near end of the truss. The truss is pulled onto temporary cribbing at the abutments and lowered into final position with jacks.
d. Two Gin Poles (method G, table VII). A single truss can be launched using two gin poles, one on the far bank and one on the near bank. Both lines are attached to the far end of the truss. The near end of the truss can be braced by the method given in c above. The truss is pulled toward the abutments. When it is near the abutments the line from the near gin pole is changed from the far to the near end of the truss and the truss is lowered to the bearing plates on the abutment sill. The advantage of two gin poles over one is that the load is under better control and there is less danger of the truss
30
"'BATTEN PLATE
F PLANK RAIL
PLANK BLOCK '
@ The lower chord members are placed on camber blocks and spliced, members in the far end of the truss.
A truck crane is placing web
@ Placing member U2R into position for bolting. Note use of hand lines.
@ Assembling web members on near end. of truss. Smaller members can be placed by hand. @ Placing member US with the truck crane. This member must be placed last because of the position of
gusset plates on adjacent members
Figure ^1. Assembling truss on bank before launching. Truck crane is used to handle members. The truss is launched from this position
when assembled. The truss is assembled with expansion end toward far bank.
31
45 FOOT POLE FRONT GUY. ONE PART 1 INCH MANILLA ROPE
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Figure 42. Gin pole-crane method of launching trusses. Note position of gin pole. Both trusses are launched with pole in this position. See figure 25 for rigging details.
4
32
591148°—44----3
Figure 43. Crane in position at near end for launching truss.
Note snub line for holding truss back and method of attaching crane line to truss.
33
® View from far bank. Timber frame on abutment end dam holds the truss upright.
® View from near bank. The timber frame shown above has been removed so crane can lower truss to abutment sill.
Figure 44- Launching truss for 90-foot bridge with gin pole and %-cubic-yard truck crane.
34
35
m k TTT k
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/• igure 45. h-frame skid support for shoring. The skid slides with the truss as it is being launched and aids in keeping the truss upright. The pin connection of shoring and skid permits the truss to turn independent of the skid.
NOTE: GUY LINES ATTACHED TO THE UPPER CHORD AND SECURED TO HOLDFASTS SUPPORT THE TRUSS LATERALLY. AS THE TRUSS
MOVES FORWARD, LINES A ARE SLACKED OFF AND LINES B ARE TIGHTENED. WHEN THE TRUSS HAS MOVED FORWARD TO POINT O', LINES A BECOME INEFFECTIVE AND LINES B SUPPORT THE TRUSS. STOP MOVEMENT AND MOVE LINES A TO A'. THIS PROCESS IS REPEATED AS OFTEN AS NECESSARY.
Figure 46. Method of attaching guy lines to support truss during launching.
36
Figure 47. Launching a truss from a position parallel to the bank. The tackle from both poles is attached to the far end of the truss. The crane can be replaced by the skid shown in figure 45.
37
Figure 48. Method of “telegraphing” heavy members into place. A line is attached to the member from both the gin pole and the crane. The member is placed by taking up line on the gin pole and paying out on the crane line.
38
® Placing a floor beam by “telegraphing”. Note hand line for guiding the beam.
@ Placing a floor beam between the trusses. A jack spreads the trusses slightly to allow the beam to slide into position. The hand line retrieves the tackle so it can be used to place the next member.
© Placing stringers after floor beams and bracing are installed. Planks are placed between lower chords as a work platform.
Figure 49. Placing floor system for 90-foot bridge. The floor system is erected in place over the gap after the trusses have been launched.
@ Installing diagonal lateral bracing after floor beams are placed. Planks are placed between floor beams to support the men at work.
39
buckling since there are two vertical components of lift in addition to the horizontal components.
e. Launching From a Position Parallel to Bank (method H, table VII). If conditions at the site are such that the trusses cannot be assembled directly behind the abutment, they can be assembled and launched from a position parallel to the bank. Figure 47 illustrates this method of launching. The equipment consists of a gin pole on each side of the stream and a truck- or tractor-mounted crane. Tackle from both gin poles is attached to the far end of the truss, on the top chord, at joint U1 and the crane picks up the near end. The crane is attached to the end post at joint Ul. The truss is swung across the gap by taking up the far-pole line, slacking off on the near-pole line, and at the same time moving the near end toward the abutment with the truck crane. The far end of the truss moves on a line between poles and since the truss is suspended from the top chord it remains upright. The A-frame skid described in paragraph c and shown in figure 66 may be used in place of the
crane. If the A-frame skid is used it should be pulled towards the near side gin pole as the truss is launched. The gin pole is moved to the left after launching the first truss to provide clearance for launching the second truss.
/. Launching by Floating Single Truss. If conditions at the site permit, a single truss can be assembled on a raft and floated into position (fig. 55). Lower chord members are placed on camber blocking high enough so the end bearings are several inches above the elevation of the abutment sill. Blocks should be placed at panel points to avoid bending stresses in lower chord members. A crane working from the bank places members in position for bolting. When assembled, shored, and tied, the truss is floated to position over the sills. It is lowered to the bearing plate by jacking, or by flooding pontons if a ponton raft is used.
g. Precautions. (1) A single truss has little stiffness in a horizontal direction. Unless precautions are taken during launching, it may buckle. Vertical lift lines to the ends of the upper chord tend
to overcome this tendency to buckle. Another precaution that may be taken is to lash heavy timbers to the upper chord to stiffen it.
(2) Trusses in place on abutments should be held by shoring and ties until the floor system is completed.
(3) Blocks on which trusses are assembled should be placed only under panel points (joints) to avoid bending stresses in the lower chord angles.
(4) The fixed end of the truss should be placed on the anchor bolts first because it is more difficult to seat. As normally assembled the fixed end is also the near end. When a crane is used for launching the truss, placing the near end first also relieves it of its critical load without delay.
54. Construction of Floor (see sheet 14 and fig. 49)
a. Placing Iloor Beams and Stringers. When trusses have been bolted to the abutments, floor beams and stringers are placed, beginning at the far end of the bridge and working towards the near
Figure 50. A 90-foot bridge partly floored. Timber approach guides should be placed as indicated to guide vehicles onto the bridge. These guides are not a part of the b/idge and must be provided separately. Note the bearing spool and hole to receive it (insert).
t
I
(
40
end. By this method work parties can lay the timber floor without having steel carried over them. Other methods may be used if conditions warrant.
b. “Telegraphing” Beams and Stringers into Place. Floor beams and stringers are handled over the gap and placed in position by a method known to steel erectors as “telegraphing” (fig. 48). The crane moves the member from the stock pile to a position behind the abutment. A line from the gin pole on the far bank is attached above the hook supporting the member. The member is picked up and placed by taking up on the gin pole line and slacking off on the crane line. Figure 49® shows a floor beam being swung across the gap by this method and figure 49@ shows a beam being placed. A jack is used to spread the trusses slightly so the beam does not have to be forced into position. Caution: Personnel should keep out of line of cables to members being placed. A failure of either cable would throw the member into anyone in line with the cable that held.
c. Placing Diagonal Lateral Bracing. Bracing is installed before stringers are placed. A plank laid between floor beams is used for support in connecting E2 and E3 to El (fig. 49). It is possible to bolt the bracing on the bank and place it as a unit.
d. Connecting Stringers to Floor Beams. Stringers cannot be placed between floor beams that have been bolted in place because of the beam flanges and the connection angles on the stringers. This difficulty may be overcome by leaving one end of one floor beam loose so it can be rotated slightly to permit swinging stringers into place (see fig. 49 and sheet 14). Stringers and beams should not be permanently bolted until stringers and beams have been placed in the two succeeding bays.
e. Installation of Floor. The procedure for laying the floor is the same as for the 30-foot bridge except that the guardrail is placed on the wearing surface. See paragraph 436 and sheet 12.
/ Wearing Surface and Protection Angle. The Wearingsurface planking is spiked to the deck. Protection angles are placed at the ends of the bridge.
g. Installation of Guardrail. Steel guardrails are set in place, centers ol bolt holes are marked, and guardrails moved aside. Holes 3 inches in diameter and 3 inches deep are bored. Holes 1 inch in diameter are bored through the remainder of deck. Bearing spools are driven into the 3-inch holes, guardrails set in place, and the guardrail bolt is driven. The O. G. washer is placed on the bolton the underside of the deck and the nut tightened. The partly floored bridge with one unit of guardrail installed is shown in figure 50.
Section III.
ERECTION BY LAUNCHING ASSEMBLED BRIDGE
55. General
Erection by this method consists of assembling the bridge complete except for timber floor and launching it as a single unit (fig. 10). A straight section of nearly level approach at least 90 feet long and
on the center line of the bridge is required if this method is to be used. An alternate method is to assemble the bridge on a raft and float it into place.
56. Assembly of Bridge
The bridge may be assembled by any of several schemes. The plan outlined on sheet 15 may be used.
57. Launching from the Bank
a. Preliminary. Preparations for launching include building skids, building cribbing, erecting a center support, and preparing rigging. Details are shown on sheets 16 and 17.
6. Procedure. The bridge is pulled over the gap until the far end icaches the center support. The overhang is supported by cantilever
Figure 51. Removal of 90-foot truss using two gin poles and truck crane. Tackle from both poles is attached to far end of truss. Note the shoring and ties on the truss still in position.
41
action. The bridge is pulled to a position directly over the abutments, the overhang again supported by cantilever action. The bridge is then blocked up on cribbing, the center support cribbing removed, and the bridge lowered to the bearing plates on the abutment sills with jacks. Placing of floor is described in section II.
58. Launching by Floating into Position
a. Preliminary. This method requires water deep enough to permit assembling the bridge on a raft and floating the raft into position. This method is practical only for a site which requires low pier construction. Preparations include building the raft and cribbing, and assembling the bridge.
b. Procedure. A raft is built with capacity sufficient to support the assembled bridge and cribbing. It is located where a crane working on the shore can place members on the raft for assembly. The bridge is assembled on cribbing high enough so it will float at an elevation slightly higher than the top of the anchor bolts on the abutments or piers. When the bridge is assembled it is floated into position and lowered to the bearing plates on the abutment sills with jacks. The tide may be used for lowering the truss if the site is on tidewater. If a ponton raft is used to float the bridge, it can be lowered by flooding the pontons (see ch. 10).
Section IV.
REMOVAL OF BRIDGE
59. General
The bridge may be removed by disassembling the floor system and taking out the assembled trusses one at a time.
60. Removing Floor System
The floor is removed in the reverse order of that in which it was assembled. Trusses must be well-shored and tied before floor beams and stringers are removed.
61. Removing Trusses
A recommended procedure for removing trusses is to use a gin pole on each bank and a crane on the near bank. The tackle from both polos is attached to the far end of the truss. This insures good control since the near-pole winch is taking up slack while the far-pole winch is slacking off. The near end of the truss is picked up by the crane. The truss can then be moved to the bank (fig. 51). This method is similar to method II discussed in paragraph 53e except that the procedure is reversed.
CHAPTER 10
MULTIPLE SPANS
62. General
The 30-, 60-, and 90-foot bridges may be built in any combination and number of units to form a multiple-span bridge. Such use is limited to a site permitting intermediate-pier construction and maximum single spans of 90-feet. No alterations or special devices are required for adapting the bridges to multiple-span construction. Figure 52 shows a multiple-span bridge built with 60-, 90-, and 30-foot bridges (also see sheet 18).
63. Pier Construction
Typical designs of intermediate piers suitable for these bridges are contained in TM 5-286 (when published). Details of a test pier are discussed below.
a. Layout of Pier. This pier was designed to support the 60-and 90-foot bridges and consisted of timber piling, caps, and sills. Because of the different dimensions and spacing of the end bearings of each bridge a special arrangement of sills is necessary. The design of the pier is shown on sheet 18.
b. Construction of Pier. The method of construction depends on the design of the pier and the condition of the site. The test pier was built in water on a mud bottom. Thirty-foot timber piling was driven using a ^-cubic-yard shovel with standard pile-driving attachment (fig. 53®). See TM 5-286 (when published) for information on piles and pile driving. Piles are cut off at the proper elevation, capped, and sills placed. Caps and sills are held in place with drift bolts.
c. Construction of Bridge Seat (fig. 53®). The bridge seat consists of bearing plates anchored to a timber sill with anchor bolts. Two factors to be considered in placing the sill are discussed below:
(1) Elevation of Floor in Adjacent Spans. Because of the difference in depth of girders and floor beams, adjustment of sill elevations must be made to bring the adjacent floor surfaces to the same elevation. Sheet 18 shows factors to be considered in'computing final elevation of sills. Adjustment is made by cutting piles at proper elevation and bolting blocks to caps to bring sills to correct elevation.
(2) Provision for Expansion. One-inch clear space between protection angles of adjacent spans must be provided to permit expansion (sheet 18). Piersand sills are spaced accordingly.
64. Launching Methods
a. Crane. One or more spans of the 30-foot bridge can be placed with a crane (fig. 53 ®). When one span has been placed it is floored and the next span is placed from it.
b. Crane-Gin Pole. The 60- and 90-foot bridges can be placed by the crane-gin pole method described in chapters 8 and 9. In most cases this method requires placing the gin pole on an intermediate pier. Various methods of using the gin pole follow:
(1) On Intermediate Pier. For the 60-foot bridge a 15-foot gin pole can be placed on the center of the pier (fig. 53 ®). Side guy lines are anchored to the pier with back guy line anchored to another pier or to the far bank. Launching the 90-foot trusses requires ar least a 30-foot gin pole, which can be placed on the pier with side guy lines anchored to special piling and back guys anchored to another pier or to the far bank.
(2) Lashed to Pier. If conditions permit the gin pole can be placed on the stream bottom. If the site is dry the gin pole is set on the ground in the usual manner. However, if under water, the gin pole must be placed on a mud shoe and the shoe lashed to the bottom of the pole.
(3) On Completed Span. If the bridge consists of two or three spans and it is possible to build from both sides, the gin pole is placed on a completed span (fig. 54). Side and back guys are anchored to the bank or to piling.
c. Floating. If site conditions permit, a practical method of erection is to assemble the bridge on a raft and float it into position. The 30- and 60-foot bridges can be erected by placing one, two, or four girders at a time. The 90-foot bridge can be erected by placing one truss at a time (figs. 55 and 56) or by assembling and floating the entire bridge into place. If a ponton raft is used the bridge can be lowered to the abutment seats by flooding the pontons.
d. Temporary Intermediate Support. The method of launching given in section III, chapter 9, may be used for erecting units of a multiple-span bridge.
65. Floor Construction
The floor design remains unchanged when the bridges are used to form multiple spans. Alternate floor designs are described in TM 5-286 (when published).
42
Figure 52. Completed multiple-span bridge consisting of the 60-, 90-, and 30-foot bridges.
43
® Placing sills and anchor bolts on intermediate pier.
® Driving pile for intermediate pier of multiple-span bridge using standard piledriving attachments. The ponton raft supports the pile-driving equipment.
® Launching 60-foot girder of three-span bridge with crane and gin pole. Note pole on intermediate pier and side guys to same pier.
® Placing girders for 30-foot span of three-span bridge with ^-cubic-yard shovel. Note intermediate pile pier.
Figure 53. Erection of multiple-span bridge.
44
Figure 54- Launching 90-foot truss for the center span of multiple-span bridge. Crane is on near approach span and gin pole on far-side approach span.
45
® Assembling truss on ponton raft. A Yz-cubic-yard shovel working from the bank places members in position for bolting. When @ The assembled truss ready to float into position,
assembled, the truss is floated into position over the supports.
@ Truss on ponton raft floated into position ready for lowering onto the pier sills. The truss will be lowered by flooding the pontons.
Figure 55. Launching a truss for the center span by floating it into position on a ponton raft. The entire 90-foot bridge can be assembled and placed in one operation by this method.
46
® Truss in position directly over the bearing plate and anchor bolts. The required clearance is provided by timber supports on which the truss is assembled (fig. 55).
@ Lowering the truss over the anchor bolts. Pontons are flooded uniformly. The fixed end must be set first.
Figure 56. Last phase of launching truss on ponton raft.
CHAPTER 11
MAINTENANCE, REPAIRS, AND STRENGTHENING
66. General
For general information on maintenance, repairs, and strengthening see FM 5-10. Specific information for these bridges is given below.
67. Maintenance
Maintenance of these bridges consists primarily of periodic inspections of the entire structure, including examination for loose nuts, and brushing and painting rust spots on the structural steel. Steel should be thoroughly cleaned by brushing with a steel wire brush. All loose rust and scale and all dirt must be removed. After cleaning, paint the spots with red load. Bridges affected by salt spray or high humidity require continuous maintenance.
68. Repairs
a. Abutments and Piers. Periodic inspection should be made to determine evidence of—
(1) Scour of banks that may endanger abutments and scour of bottom that may weaken piers. Where this condition exists repairs should be made to reduce the tendency to scour by one of the following methods:
(a) Riprap.
(6) Dumping large stones into the stream.
(c) Channel improvements. .
(2) Failure of structural timbers used for footings, abutments, piers, or floors. This may be caused by decay, rot, excessive load, or structural defects. Repairs should be made by replacing the members.
b. Structural Steel. Only damage caused by accidents is cause for repairs.
c. Timber Floor. Repairs consist mainly of replacing the wearing surface. This should be done before traffic damages the laminated deck.
69. Strengthening
There are no special provisions for strengthening or reinforcing these bridges.
47
PART THREE APPENDIX
TABLES II TO XVIII
Table II. Weights and dimensions
Bridge Structural steel Connections Lumber
Total weight in pounds Weight of one girder in pounds Weight of one truss in pounds Cubage Maximum length of one piece Maximum weight of one piece in pounds Total weight in pounds Cubage Number of boxes Total quantity in 1,000-feet board measure Cubage Maximum length of one piece
Cubic feet Ship tons Cubic feet Ship tons Cubic feet Ship tons
30-foot 12, 172 42, 686 56, 927 2, 600 10,000 292.17 7. 31 31'-6" 2, 554 745 9. 5 0. 24 6 3. 868 322. 3 8. 05 16'-0"
60-foot 781. 54 19. 55 25'-l%" 3, 495 3, 102 30. 5 0. 76 20 7. 544 628. 7 15. 70 16'-0"
90-foot 15, 000 1, 896. 56 47.40 29'-ll1K6" 1, 655 4, 727 46. 5 1. 16 31 10. 608 884. 0 22. 10 16'-0"
Table III. Transportation
(Structural steel, fasteners, and fittings only)
Method
30-foot bridge
60-foot bridge 90-foot bridge
Vehicle: Trailer, full, flat-bed, 8-tou with prime mover. Number of loads 2 4 7
Vehicle: Trailer, full, flat-bed, 16-ton with prime mover. Number of loads 1 3 5
Rail: 1 Standard U. S. freight car—military. Rail: Standard U. S. freight car—commercial. Two 20-ton flat. One 50-ton gondola.3 Three 20-ton flat.2 One 50-ton gondola.3 Four 20-ton flat.2 One 70-ton gondola.
1 Length of members requires placing the load on one car with the overhang extending over an idler car.
2 Car loading for the 60- and 90-foot bridges depends on method of loading. Bulk, not weight, is the determining factor.
2 The 30- and 60-foot bridges can be transported together in one 70-ton gondola.
48
Table IV. Packaging of materials for 30-foot I-beam bridge 1
Description of unit Mark How packed Number Weight (pounds) Cubage 2 (cubic feet)
Units per span Units per package Packages per span Per unit Per package Per span Per package Per span
Girder Plate, bearing Clip, traction Diaphragm, intermediate Diaphragm, end Angle, protection Clip, floor Bolt, erection, rough, diameter by 2" long, thread 1%", square head, 1 square nut. Washers, cut, for diameter bolt Bolt, anchor, 1" diameter by l'-6" long Bolt, structural, ribbed, diameter by 2X6" long, buttonhead, 1 hexagon nut. Bolt, structural, ribbed, diameter by 2%" long, countersunk head, 1 hexagon nut. Bolt, standard, diameter by l'-7%" long, threaded 3", hexagonal head, 1 hexagon nut. 2 0. G. washers 1%" diameter SAE lock washer. Nails, 50d, cement-coated Total Gl BP1 Cl Dl D2 Al x > 7 \ ► 7 Loose (3) (3) Bundle Bundle Bundle Box Box Box Box Box 4 8 8 6 6 4 130 ' 50 ' 75 L 16 f 160 1 20 30 3, 600 1 2 2 2 2 4 130 50 75 16 160 20 30 1, 800 3 3 1 1 X > 1 7 X > 1 1 2 2, 554 31 8 128 105 42 0. 71 0. 96 0. 13 4. 30 r 0. 95 0. 98 6. 6 0. 0625 2, 632 256 210 168 130 X > 136 7 172 198 112^ 10, 216 248 64 768 630 168 92 ' 48 10 I 78 ' 152 20 198 225 67. 5 4. 93 2. 16 0. 91 1. 50 X > 1. 50 j 2. 00 1. 50 1. 50 270. 00 14. 78 6. 48 0. 91 1. 50 1. 50 2. 00 1. 50 3. 00
-- 17 12, 917 (4) 301. 67
1 Does not include lumber (3868 b.m., bill of material, sheet 1). Requisition lumber separately.
2 Over-all total cubage may be slightly reduced by properly stacking bridge pieces.
2 Bolted to Gl.
4 Add 100 pounds for weight of boxes.
Table V. Packaging of materials for 60-foot I-Beam bridge 1
Description of unit Mark How packed Number Weight (pounds) Cubage 2 (cubic feet)
Units per span Units per package Packages per span Per unit Per package Per span - Per package Per span
Girder, section, outer end Plate, bearing Splice plate, flange Splice plate, web Plate, fill Clip, traction Girder, section, outer, end Plate, bearing Splice plate, flange Splice plate, web Plate, fill Clip, traction G2R BP1 Loose Bolted to G2R_ X 2 1—11—1 CO CM N r-1 T—< CO < —-—XX ■' X. > 2 (3, 075 31 >3, 115 >3, 115 6, 230 6, 230 52 5 105 0
C2 G2L BP1 Loose Bolted to G2L_ i. > 2 > 2 I 9 (3, 075 31 - --- 52. 5 105. 0
C2 2 2 . 1 I 9
See footnotes at end of table.
49
Table V. Packaging oj materials J or 60-joot I-Beam bridge 1—Continued.
Description of unit Mark How packed Number Weight (pounds) Cubage 2 (cubic feet)
Units per span Units per package Packages per span Per unit Per package Per span Per package Per span
Girder, section, inner, end Plate bearing G4 BP1 Loose > 4 J 2 2 14 1 6 54 f 18 1 720 1 2 I 14 6,400 ( 1 1 J 3 2 2 1 1 1 2 1 2 27 18 720 2 14 1, 600 > 4 7 2 2 7 1 3 2 > 1 4 (3, 065 31 — 3, 105 3, 491 3, 495 308 154 264 178 78 94 5 6 100 12, 420 6, 982 6, 990 j 2,310 792 356 78 94 5 6 400 52. 5 73. 2 73. 2 f 7. 37 1 3.61 3. 08 1. 50 X > 1.80 1. 50 210. 0 146. 4 146. 4 51. 59 3. 61 9. 24 3. 00 1. 80 6. 00
Splice plate, flange Splice plate, web _ Bolted to C4
Plate, fill
Clip, traction _ C2 G3 G5 D3 D3 D4 AB1 1 9 3, 491 3, 495 154 154 132 6. 6 ( 4. 3 1 0. 13 ] 2. 50 (0. 423 0. 0625
Girder, section, outer, center Girder, section, inner, center Diaphragm, intermediate Diaphragm, intermediate Diaphragm, end Bolt, standard, diameter by l'-7%" long, threaded 3", hexagonal head, 1 hexagonal nut, 2 0. G. washers, 1%" diameter SAE lock washer. Bolt, anchor, 1" diameter by l'-6" long Washer, cut, for diameter bolt Turnbuckle (spare) Nut, 1" diameter (spare) Nails, 50d. cement-coated •_ Total Loose Loose Bundle Loose Bundle Box >Box Box
46 3 45, 788 812. 04
Angle, protection Bracing, lateral, diagonal Bracing, lateral, diagonal Clip, floor Al T1 T2 Bundle Bundle Bundle,- Box
4 12 12 230 425 330 400 f 20 1 190 540 4 12 12 230 142 165 200 20 190 135 1 1 1 1 3 2 2 } 1 4 42 21. 6 18. 9 0. 85 1. 12 0. 95 1. 04 f 1.01 1 1. 10 1. 13 168 259 227 196 159 157 208 >229 152. 5 168 259 227 196 476 314 416 229 610 0. 90 1. 80 1. 60 1. 70 1. 50 1. 50 1. 50 1. 50 1. 50 0. 90 1. 80 1. 60 1. 70 4. 50 3. 00 3. 00 1. 50 6. 00
Bolt, erection, rough, diameter by 3" long, threaded 2%", square head, 1 square nut. Bolt, structural, ribbed, Vfi diameter by 21/{6" long, buttonhead, 1 hexagon nut Bolt, structural, ribbed, diameter by 2%" long, buttonhead, 1 hexagon nut. Bolt, structural, ribbed, diameter by 2%6,/ long, countersunk head, 1 hexagon nut. Bolt, structural, ribbed, %" diameter by 3" long, countersunk head, 1 hexagon nut. Bolt, structural, ribbed, %" diameter by 3%6" long, countersunk head, 1 hexagon nut. 1 Box Box Box Box Box
1 Does not include lumber (7544 bm, bill of material, sheet 5). Requisition lumber separately.
2 Over-all total cubage may be slightly reduced by properly stacking bridge pieces.
3 Add 250 pounds for weight of boxes.
50
Table VI. Packaging of materials for 90-foot truss bridge 1
Description of unit Mark How packed N umber Weight (pounds) Cubage 2 (cubic feet)
Units per span Units per package Packages per span Per unit Per package Per span Pet-package Pet-span
Post, end, sloped U1R Loose 2 1 2 740 740 740 740 1, 480 1, 480 4, 908 3, 310 1, 129 1, 129 3, 178 2, 932 1, 129 1, 129 1, 172 2, 376 1, 296 1,616 1, 132 344 28. 95 28. 95 41 72 57. 90 57. 90 166. 88 89. 18 101. 43 101 43
Post, end, sloped U1L Loose 2 1 2
Chord section, upper, end U2 Loose 4 1 4 1, 227 1, 655 1, 129 1, 129 1, 589 1, 466 1, 129 1, 129 293 1, 227 1, 655 1, 129 1, 129 1, 589 1, 466 1, 129 1, 129 293
Chord section, upper, center U3 Loose 2 1 2 44. 59 101 43
Chord section, lower, end L1R Loose 1 1 1
Chord section, lower, end .. LIL Loose 1 1 1 101 43
Chord section, lower, center L2R Loose 2 1 2 96 06 192 12
Chord section, lower, center L2L Loose 2 1 2 95 40 190 80
Chord section, lower, end L3R Loose 1 1 1 101 43 101 43
Chord section, lower, end L3L Loose 1 1 1 101 43 101 43
Vertical, web_ Pl Loose 4 1 4 3 98 15 92
V ertical, web P2 Loose 8 1 8 297 297 4. 27 34 16
Vertical, web P3 Loose 4 1 4 324 324 4 45 17 80
Diagonal, web Wl Loose 8 1 8 202 202 5 22 41. 76 20 80
Diagonal, web W2 Loose 4 1 4 283 283 5 20
Diagonal, web . . W3 Loose 2 1 2 172 172 15 04 30 08
Diagonal, web W4 Loose 2 1 2 69 69 138 1 26 2 52
Diagonal, web W5 Loose 2 1 2 67 67 134 1 22 2. 44 57 66
Beam, floor, end _ _ Bl Loose 2 1 2 1,093 1, 146 77 1, 093 1, 146 693 2, 186 9, 168 693 28 83
Beam, floor, intermediate B2 Loose 8 1 8 25 26 202 08
Bracing, lateral, diagonal El Bundle 9 9 1 4 43 4 43
Bracing, lateral, diagonal E2 Bundle 9 9 1 37 333 333 2 16 2. 16 21 15
Bracing, lateral, diagonal E3 Loose 9 1 9 46 52 46 414 2.35 1 40
Angle, protection _ . _ . A2 Bundle 4 4 1 208 208 1 40
Guardrail _ _ A3 Bundle 18 2 9 241 482 4, 338 172 6. 60 59. 40
Plate, bearing BP2 Bolted to chord 4 1 43
Stringer Si sec. Loose 18 1 18 242 242 4, 356 5, 004 234 5 57 100 44
Stringer S2 Loose 18 1 18 278 278 6. 77 1 50 121 86
Clip, floor Box 330 330 1 0 71 234 1. 50 1. 50
Bolt, anchor, 1" diameter by l',-6" long Washer, cut, for diameter bolt | AB1 Box ( 10 < 975 10 975 j 1 ( 4. 30 <0111 j>208. 0 ( 43. 0 < 108 0 | 1. 50
Washer, bevel (2 sizes) [ 220 220 ( 0 27 ( 57 0
Spool, bearing Box 186 62 3 3 70 229 688 1 50
Nails, 50d, cement-coated Box 11, 200 650 1600 7 0 0625 100 0 700 1 50 10 50
Bolt, erection, rough, diameter by 2%" long, threaded 2 Yff, square head, 1 square nut. Bolt, structural, ribbed, diameter by 1%" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, %" diameter by 2%" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, diameter by 2%" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, %" diameter by 1 long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, %" diameter by 1%" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, diameter by 2%" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, %" diameter by 2%6" long, buttonhead, 1 hexagonal nut. Bolt, structural, ribbed, diameter by 2 1%6,/ long, buttonhead, 1 hexagonal nut. Bolt, standard, 1" diameter by 11" long, threaded 3", hexagonal head, 1 hexagonal nut, 1 0. G. washer, 1" diameter SAE lock washer. Total Box 217 3 0. 74 160 481 1. 50 4. 50
40 40 0. 588 24
Box 70 70 1 0. 657 128' 46 1. 50 1. 50
80 80 0. 726 58
Box 780 260 3 0. 611 159 477 1. 50 4 50
Box 310 310 1 0. 634 197 197 1 50 1 50
Box 370 185 2 0. 680 126 252 1. 50 3. 00
Box 350 175 2 0 703 123 246 1 50 3 00
Box 280 280 1 0 749 210 210 1 50 1 50
Box 186 31 6 5. 1 158. 0 949 1. 50 9. 0
150 — 3 61, 654 1, 943. 06
1 Does not include lumber (10, 608 bm, bill of material, sheet No. 8). Requisition lumber separately. 2 Over-all total cubage may be slightly reduced by properly stacking bridge pieces. 2 Add 450 pounds for boxes.
51
Table VII. Erection methods and equipment.
Table VII. Erection methods and equipment—Continued.
Table VII. Erection methods and equipment—Continued.
Method A: 30-Foot Bridge
Crane or derrick
Method D: 60-Foot Bridge
Gin pole (single or double girder)
Method F: 90-Foot Bridge
Gin pole—(single truss)
(Exclusive of construction of abutments, piers, or approaches)
Equipment Remarks
Quantity Minimum safe capacity Description
1 1 y tons at 20 ft. Crane or derrick %-cu.-yd. Quick way crane is adequate (see table XV).
Method B: 30-Foot Bridge
Skidding (Single or double girder)
1 5,000 lb Truck or tractor winch- 4-ton cargo truck
2 5 tons Jacks„_ Erection lumber with winch or D4 tractor with winch. See table IX.
Method C: 60-Foot Bridge
Gin pole- crane (single or double girder)
1 1 10 tons 5 tons at 10-ft. radius. 30-ft. gin pole _ _. Crane or derrick
1 15,000 lb Truck or tractor winch-
1 — Air compressor
500 ft_ 3 48 500 ft.. 3 3 2% tons 10 tons 1 ton 4 tons 4 tons %-in. wire rope %-in. steel single block - _ %-in. wire-rope clip 1-in. manila rope 1-in. rope, double block. 1-in. rope, single block._ Tools for steel erection. Erection lumber k . 1
%-cu.-yd. Quickway crane is adequate (see table XV).
4-ton cargo truck with winch or D4 tractor with winch.
With attachments. 105 cfm min.
6x19 plow steel.
See table VIII.
See table IX.
Equipment Remarks
Quantity Minimum safe capacity Description
1 Tractor J ack D4 or larger. For lowering girder (or girders). Other eq uipment same as method C except for elimination of crane.
2 5 tons
See method C
Method E: 90-Foot Bridge Gin pole—crane (single truss)
1 1 2 1 900 ft_ 3 48 500 ft. 3 3 10 tons 5 tons at 15 ft. 15,000 lb 2% tons 10 tons.. 1 ton 4 tons 4 tons 45-ft. gin pole Crane, truck, or tractor. Truck or tractor winch. Air compressor %-in. wire rope %-in. steel single block. _ %-in. wire-rope clip 1-in. manila rope 1-in. rope, double blocki-in. rope, single block. _ Tools for steel erection. Erection lumber and hardware. 30-ft. pole can be used. %-cu.-yd. Quickway is adequate if used with caution. 4-ton cargo truck or D4 tractor. With attachments. 105 cfm min. 6 x 19 plow steel. See table VIII. See table IX.
Equipment Remarks
Quantity Minimum safe capacity Description
1 2 1 900 ft. 3 48 500 ft_ 3 3 2 10 tons 15, 000 lb 2% tons 10 tons 1 ton 4 tons 4 tons 5 tons 45-ft. gin pole Truck or tractor winch. Air compressor %-in. wire rope %-in. steel single block.. %-in. wire rope clip 1-in. manila rope 1-in. rope, double block. 1-in. rope, single block. Tools for steel erection. Erection lumber and hardware. Jacks 4-ton cargo truck or D4 tractor. With attachments. 105 cfm min. 6x19 plow steel. See table VIII. See table IX.
Method G: 90-Foot Bridge Two gin poles—(single truss) Same as method F except rigging is doubled.
Method H: 90-Foot Bridge
Restricted approach—(single truss) Same as method G plus truck or tractor crane.
Method I: 90-Foot Bridge
Assembled bridge—(two trusses and floor system)
800.__ 1_ 2% tons %-in. wire rope 6 x 19 plow steel. Will depend on site. See sheets 16 and 17.
10 tons %-in. double block (steel). %-in. single block (steel). %-mch wire rope clip Winch
1 10 tons
24-__
1 15,000 lb 12 tons
4 Jack Erection lumber and hardware.
52
Table VIII. Tools jor steel erection1
30-Foot I-Beam Bridge
N ame Size Number required Remarks
Spud wrench 24 in. bv 1%6 in 6 For erection bolts.
Ratchet socket 24 in. by 1%6 in 4 For ribbed bolts.
wrench.
Crescent wrench 15 in 2
Driftpins .. 1%6-in. dia 12 6 in. long.
Sledge 8 lb __ 2
Hammer 3 lb 2
Shackle 1 in 6
Connecting bar_ _ 3 ft 4
Sling 7 ft 3 %-in. wire rope.
J ack 10 ton 2
Pinch bar_ 5 ft 2
60-Foot I-Beam Bridge
Spud wrench 24 in. by 1%6 in 8 For erection bolts.
Ratchet socket 24 in. by 1%6 in 6 For ribbed bolts.
wrench
Crescent wrench 15 in 8
Stillson wrench 24 in 2 For installing lateral
bracing.
Driftpins TL-in. dia 60
Sledge 8 lb 6 6 in. long.
Hammer 3 lb 6
Shackle 1 in 6
Connecting bar 3 ft 4
Sling 10 ft„ 4 %-in. wire rope.
Jack, track 10 ton 2 Simplex type.
Pinch bar 5 ft 2
Table IX. Bill oj material-for erection 1
30-Foot I-Beam Bridge
Method Size Quantity Board feet Remarks
A and B_ 3" x 12" x 14' -0"__ 6 ea__ 252 Used for skidding stringers, blocking, and bracing.
60-Foot I-Beam Bridge
C and D_ J3" x 12" x 14' -0"__ 110" x 10" x 16' -0"_ 12 ea__ 3 ea 504 399 (For blocking and J bracing.
90-Foot Truss Bridge
E, F, G, and H 3" x 12" x 14' -0"_ 6" x 6" x 16' -0"__ 10" x 10" x 16' -0"_ %" carriage bolts 6%" long. 60d spikes 20 ea_ 8 ea 3 ea__ 30 100 lb 840 288 399 For blocking, brac-> ing, and erection frames.
1 Based on average conditions.
90-Foot Truss Bridge
Spud wrench, _ 24 in. by 1% in 18 For erection bolts.
Ratchet socket 24 in. by 1% in 9 For ribbed bolts.
wrench
Crescent wrench 15 in _ _ __ 6
Driftpins % in 100 6 in. long.
Sledge 8 lb 6
Hammer 3 lb 6
Connecting bar 3 ft 8
Shackle 1 in 6
Sling _ _ _ 4 ft 3 %-in. wire rope.
Sling 8 ft 3 %-in. wire rope.
Chain hoist 1 ton 2
Jack, journal 15 ton 2
Jack, track 10 ton 2
Pinch bar 5 ft 2
1 Supplemented by organic equipment normally required for construction.
53
Table X. Normal troop requirements 1
Bridge Noncommissioned officers Units Drivers Operators Average man-hours
No. Equipment No. Equipment Remarks
1 S Sgt 1 4-ton cargo truck 1 Tractor —
30-foot ■ i Sgt 1 squad 1 2%-ton cargo truck, __ 1 Crane 453
i dpi 1 Compressor
1 Crane
1 S Sgt 2 Sgts 2 Cpls 1 4-ton cargo truck 1 Tractor Crane May need pile driver or
60-foot 2-squads 2 2%-ton cargo truck 1 earth auger for abut-
1 Compressor, 1, 042 ments. One squad can
I 1 Crane build bridge but will
1 S Sgt 3 Sgts 1 4-ton cargo truck 1 Tractor Crane take longer.
90-foot ■ 1 platoon 3 2%-ton cargo truck,. 1 1, 929 Two squads can build
3 Cpls 1 Compressor,, bridge by increasing
1 Crane number of work days.
— 1
1 Conditions (a) (b) (0 Includes work in unloading, construction of simple abutments, and erection Quantities based on average site and working conditions and troops with little experience in steel erection Extra men are used during some periods to expedite work. See tables XI, XII, and XIII
Table XI. Specimen work sheet—30-Joot bridge 1
Totals
Distribution of labor 2
Subdivision of work
NCO
EM
Total hours
Total manhours
First day
Second day
Third day
Fourth day
0800 11000
1000;1300 1500 120011500 1700
0800
1000
1000
1200
1300
1500
1500 0800'1000 ’""9 120(J
1700 1000
1300
1500
Unloading steel at site _________
Survey for abutment location_____
Construction of timber abutments 3. Placing girders with crane_)_____
Placing and bolting diaphragms___
Constructing laminated timber deck
Constructing curbs_______________
1
1
2
1 1
1
1
4 1
4 2
12 | 10
4 1
12 2
8 6
8 2
5
10
140
5
26
54
18
Laying wearing surface_____________
Installing protection angles_______
Final clean-up of construction area. Supervision of job_________________
Tool corporal______________________
Tractor operator___________________
Crane operator.*___________________
Drivers________________________
1
1
1
1
1
8 1
4 1
12 1
22
22
1 22
1 16
4 22
5
13
22
22
22
16
88
©
1500
1700
Remarks
6 men on each abutment.
2 men on each end.
3 two-man erection bolt details.
3 two-man ribbed bolt details.
4 men carrying 2- by 6-inch plank.
4 men nailing 2- by 6-inch plank.
3 men on each curb drilling holes and placing bolts.
1 two-man detail sawing, carrying and placing timbers.
2 men carrying 2- by 12-inch plank.
3 men on each side nailing plank.
2 men each end.
Senior NCO.
Crane released after girders have been launched.
©
© □
©
o
©
9
a □
fXZXX* ">1">W‘nE W “ “ttle *" NCO'a; (k) Work ls U.,„ ,n slogle daJ ttae shins;
2 Spare men are used for special tasks not shown in the table.
©-Xhoured On C°nStrUCtiOn °f Simple timber Bbutment-’ Wo^er types are built the data may vary considerably. Site conditions may effect these data.
3—Second hour.
•—Full time.
54
Table XII. Specimen work sheet-—60-joot bridge 1
Table XIV. Loads on abutments 1
Troops
Distribution of labor 2
Subdivision of work
NCO EM
Total hours
Total manhours
First day
Second day
Third day
0800 1000 1300'1500 1000 1200 1500 1700
0800 * 1000'130011500 1000 1200 1500 1700,
0800' 1000
'1000 1200
Fourth day
13Oo'15OO 0800'1000' 1500 1700 1000 1200
Fifth day
Remarks
1300
1200 1500
1500 0800 1000 1300
1700 1000(1200 1500
1500
1700
Unloading steel at site'___________________________
Survey for abutment location_______________________
Construction of timber abutments 3_________________
Assembly of gin pole_______________________________
Erection of gin pole_______________________________
Assembly of girders________________________________
Launching girders__________________________________
Removing gin pole__________________________________
Placing & bolting diaphrams________________________
Placing lateral bracing___?------------------------
Constructing laminated deck________________________
Constructing curbs_________________________________
Laying wearing surface_____________________________
1 4
1 4
2 12
1 4
1 8
2 12
2 6
1 6
1 6
1 6
1 8
1 8
1 8
Placing protection angles_________
Final clean-up of construction area. Supervision of job________________
Tool corporal_____________________
Tractor operator__________________
Crane operator____________________
Drivers___________________________
1 4
4 24
1 _______
1 _______
1
1
5
2
2
12
6
2
12
8
3
6
2
10
3
3
1
1
37
37
37
24
37
10
10
168
30
18
168
64
21
42
14
90
27
27
5
28
37
37
37
24
185
6 men on each abutment.
© © © © ©
©
30-foot bridge (pounds) 60-foot bridge (pounds) 90-foot bridge (pounds)
Required abutment capacity Maximum reaction on one bear- 2 141, 000 3 165, 000 4 177, 000
ing plate 5 56, 800 5 68, 750 6 100, 000
3 four-man bolting details.
3 men at each end.
3 two-man bolting details.
2 three-man details.
4 men carrying, 4 nailing.
2 men constructing timber curb.
3 men bolting each curb.
2 men men carrying.
2 three-man nailing details.
2 men each end.
Senior NCO.
Crane released after girders have been launched.
1 In multiple-span construction the total load on an intermediate pier is the sum of the abutment loads for the spans resting on the pier. '
2 Includes dead load of 16,000 pounds, live load of 100,000 pounds, and impact at 32 percent.
3 Includes dead load of 40,000 pounds, live load of 100,000 pounds, and impact at 32 percent.
4 Includes dead load of 52,000 pounds,- live load of 100,000 pounds, and impact at 25 percent.
5 Bridge has four bearing plates at each end.
6 Bridge has two bearing plates at each end.
1 Data in the table are based on the following conditions:
Troops have had little experience in steel erection but are supervised by experienced noncommissioned officers.
Work is done in single 8-hour daytime shifts.
Weather conditions are favorable.
Crane-gin pole method of launching girder is used.
2 Spare men are used for special tasks not shown in the table.
3 Data are based on construction of simple timber abutment. If other types are built the data may vary considerably'. Site conditions may effect these data.
©—First hour.
Q—Second hour.
•—Full time.
Table XIII. Specimen work sheet-—90-joot bridge 1
Troops
Distribution of labor 2
Subdivision of work
NCO
EM
Total hours
Total manhours
First day
Second day
Third day
Fourth day
Fifth day
Sixth day I Seventh day
0800
1000
1000 1300 1500 0800 1000 13Oo|15OO 0800 1000 1300
1200 1500 1700 1000 1200 1500 1700 1000 1200 1500
1500 0800 1000 1300 1500 0800
1700 1000 1200 1500 1700 1000
1000 13Oo!15OO
1200 1500 1700
0800 1000 1300 1500 0800 1000 1300 1500 1000 1200 1500 1700 100011200 1500,1700 _ 1
Unloading steel at site ... . _
Survey for abutment location _ _ Construction of timber abutment 3>4. Assembly of gin pole______________
Erection of gin pole______________
Assembly of first truss 5_________
Assembly of second truss8_________
Launching of first truss 6________
Launching of second truss 6_______
Erection of floor system 2________
Bolting floor system 8____________
Removal of gin pole_______________
Construction of laminated deck 9__
Placing wearing surface 10________
Placing guard rail11______________
Placing protection angles 12______
Final clean-up of area____________
Supervision 13____________________
Tool corporal_____________________
Tractor operator__________________
Crane operator 14_________________
Drivers___________________________
i Data in this table are based on the following conditions:
Troops have had little experience in steel erection but are supervised by experienced NCO’s.
Work is done in single 8-hour day shifts.
Weather conditions are favorable.
Crane gin-pole method of launching is used.
2 Spare men are used for special tasks not shown in the table.
©—First hour.
3 Data based on construction of simple timber abutments. If other types are built the data may vary considerably. Site conditions may effect these data.
4 6 men at each abutment.
8 4 three-man bolting details.
8 4 men at each abutment and 4 men on guys.
7 6 men placing members and 3 men assisting.
(J—Second hour.
8 6 two man bolting details.
8 4 men nailing, 4 men carrying.
28 3 men each side, 2 men carrying.
ii 4 men carrying, 2 men marking, 2 men drilling, 4 men bolting.
42 2 at each end.
13 Senior NCO.
14 Crane released after floor system has been placed.
•—Full time.
55
Table XV. Crane capacity data
Quickway (Coleman) % Cu. Yd., 25-Ft. Boom
Radius (feet) Safe load (pounds)
Side End
Without outrigger With outrigger
10 6, 700 11 000 11 000
15 4, 700 6 500 6 500
20 3, 200 4 700 4 700
25 2, 300 3, 400 3, 400
Buckeye Model 70, % Cu. Yd., 35-Ft. Boom
Radius (feet) Safe load (pounds)
10 13, 600 8, 600 5, 850 4, 350 3, 550 3, 000
15
20
25
30
35
Osgood Model 20, 35-Ft. Boom (With 1,100-Lb. Counterweight)
Radius (feet) Safe load (pounds)
10 13, 840 11, 500 6, 750 4, 570 3, 490 2, 700
12
15
20
25
30
2, 340
Table XVI. Winch data
Equipment Winch capacity 1 Cable Gross 2 weight of vehicle (pounds)
Bare drum (pounds) Full drum (pounds) Diamteer (inches) Length (feet)
Truck, command and reconnaissance, %-ton, 4x4 5, 000 5, 000 5, 000 5, 000 10, 000 10,000 10,000 10, 000 10, 000 10,000 10,000 10, 000 10, 000 15, 000 15, 400 25, 000 32, 000 % % % % y y /2 X % y y % k % I % I % 1 7/ I /8 ( 7/ J /8 1 1 250 250 250 250 250 250 250 250 250 250 250 250 250 250 485 335 420 300 375 280 5, 600 5, 775 7, 175 10, 500 11, 500 12, 500 12, 500 12, 500 16, 200 15, 350 16, 850 20, 200 15, 450 26, 500 } 15,000 } 22, 600 | 32, 900
Truck, weapon carrier, %-ton, 4x4
Truck, command, %-ton, 4x4
Truck, cargo and personnel carrier, 1%-ton, 6x6
Truck, cargo, 1%-ton, 4x4
Truck, dump, 1%-ton, 4 x 4 Truck, earth auger, 1%-ton, 4 x 4, Ml.
Truck, earth borer and pole setter, 1%-ton, 4x4, K-44. I ruck, cargo, L. W. B., 2%-ton, 6x6, with wrecker set No. 7 and winch
Truck, cargo, S. W. B., 2%-ton, 6x6
Truck, dump, L. W. B., 2%-ton, 6x6
Truck, cargo, 2%-ton, 6 x 4 Truck, cargo, L. W. B., 2%-ton, 6x6
Truck, cargo, L. W. B., 4-ton, 6 x 6. w/w
D4 Towing winch
8, 580 14,000 22,000
D6 (Hvster)
D7 (Hvster)
_========^==
1 Data based on information given in TM 9-2800. — 2 Carrying rated pay load.
TABLE XIII. Working stresses1 for structural carbon steel (A. S. T. M.-A7) 2 used in design of bridges
Kind
Unit stress in pounds per square inch
Table XVIII. Working unit-stresses for treated timber used in design of bridge floors 1
Bucyrus-Erie Model 15-B % Cu. Yd. (Counterweight A)
Radius (feet) Safe load (pounds)
30-ft. boom 35-ft. boom 40-ft. boom
10 11, 700 8, 860 11, 625 8, 800
12 8, 700
15___
6, 420 4, 310 6, 350 4, 235 6, 275 4, 160
20
25 3, 240 3, 165 3, 100
30 2, 470 2, 400 2, 325 1, 910
35
Axial tension, structural steel, net section______
Tension in extreme fibers of rolled shapes, girders, and built sections subject to bending______________
Axial compression, gross section_________________
Compressions in extreme fibers of rolled shapes, girders, and built-up sections subject to bending (for value of not greater than 40)________________
L = length in inches of unsupported flange between lateral connections. 6=flange width in inches.
Shear in power-driven rivets and pins_____________
Shear in turned bolts________________________
Bearing on turned bolts________________________
22,500
22,500
22,500
22,500-3.75=^ tr
16,875
13,750
25,000
i Increased 25 percent over A. A. S. H. O. 1941 specifications.
2 Plates, sections, and bars:
Tensile strength _ _________________________________
Yield point, minimum_____________________________
but in no case less than______________
60,000 to 72,000 p. s.
0.5 tensile strength.
33,000 p. s. i.
Grade and species Fiber stress in bending or tension (pounds per square inch) Maximum horizontal shear (pounds per square inch) Compression perpendicular to grain (pounds per square inch)
1800 No. f dense select structural Douglas fir or prime structural yellow pine (long leaf or dense short leaf) 1, 800 120 380
1 A. A. S. H. O. 1941 specifications.
56
PART FOUR
GENERAL AND DETAILED DRAWINGS
Sheets 1 to 12 inclusive contain details of the design of the 30-, 60-, and 90-foot bridges. These are taken from the following Engineer Board drawings:
30-foot I-beam bridge—Plan No. D-2656-1 and No. D-2656-2, revised 8-27-43 and 11-2-43.
60-foot I-beam bridge—Plan No. D-2657-1 and No. D-2657-2, revised 8-26-43, 9-18-43, and 11-2-43.
90-foot truss bridge—Plan No. D-2658-1, No. D-2658-2, No. D-2658-3, and No. D-2658-4, revised 11-2-43 and 11-13-43.
Information contained in bills of materials and other details is the latest available and supersedes data contained in TB ENG 12, 15 March 1944.
Sheets 13, 15, 16, and 17 contain information furnished by the Engineer Board on assembly and erection of all three bridges.
Sheets 14 and 18 contain information on assembly and erection obtained from tests made jointly by the Engineer School and the Engineer Board.
57
SHEET NO. 1
30-FOOT I-BEAM BRIDGE BILL OF MATERIAL AND BOLTING DETAILS
MARK 1IN.T BRIDGE, WITHOUT LUMBER UNH SET STOCK NO. 2OOO-IOO UNIT WEIGHT POUNDS NO. REQ'D TOTAL WEIGHT POUNDS
Gt Girder 2,554 4 10,216
Dt Diaphragm , intermediate 128 6 768
D2 Diaphragm, end 105 6 630
Al Angle, protection 42 4 168
BP! Plate, bearing 3/ 8 248
AB! Bolt, anchor 43 18 78
Cl Clip, traction 8 8 64
Clip, floor 0.71 130 92
Bolt, erection , rough, 7/8" dia.x 2", threaded I1/2", sq. head, / sq.nut 0.96 50 48
Bolt, structural, ribbed 7/8" dia. x2 16”, buttonhead, / hexagonal nut 0.95 160 152
Bolt, structural, ribbed, 7/8" dia.x21/4“, countersunk head J hexagonal nut 0.98 20 20
Bolt assembly, euro 6.6 30 198
Washers, cut, for 7/b" dia. bolts 0.13 75 !0
Nails, 50d, cement-coated 0.0625 3600 225
TOTAL METAL IN BRIDGE SET 12,917
LUMBER (MUST BE REQUISITIONED SEPARATELY) FEET B.M. EACH GROSS QUANT NO. REQ'D TOTAL M.B.M. GROSS QUANT.
LAMINATED FLOOR SYSTEM
Lumber, rough, 2"x 6"x 14'-0" 14 210 2.940
Lumber, rough, 2" x 12"x 15'~ 9" 32 12 0.3 84
Lumber, rough , 2" x 12" x 12'- 0" 24 4 0.096
Lumber, rough, 2"x 12"x 9'~ 9" 20 8 0.160
Lumber, rough , 6"x 6"x I6'~C" 48 4 0.192
Lumber, rough, 4" x 6"x 4'~ 0" 8 12 0.096
TOTAL LUMBER 3.868
NOTE: One M.B.M. equals one thousand board feet.
RIVET BOLT DETAILS
SECTION S-S
LENGTH
= o w
CHECKING WORKING THICKNESS
co (/>
HEIGHT
---C---
OF NUT
GRIP OF THREAD
LENGTH,
Ixl Q cc III co 1- (D
cn > c War
3
O — O O
HEXAGONAL NUT
STRUCTURAL RIBBED BOLTS
CONNECTION
GRIP (INCHES)
LENGTH
DIAPHRAGM, END, TO GIRDER WEB
DIAPHRAGM , INTERMEDIATE , TO GIRDER WEB
CLIP, TRACTION, TO GIRDER, TOP FLANGE
ALL BOLTS Zg" DIAMETER
32
2 /I6
16
58
30-FOOT I-BEAM BRIDGE PLAN AND SECTION
SHEET NO. 2
| Bearing
Symmetrical about- of Span
3O'-Q' ctoc bet rings
1(7-0'
Wearing surface 2'xl2'i
Protection angle (flfl
Traction dip (flfl — End diaphragm (flfl '
2-50 d cement -coated nails per sg ft
Symetrica! about center line of bridge
l5'-9‘rl5'-9’ 1 ,,
9'-9‘-rl2'-0“-i9‘-9'] alternating
HALF-PLAN AT TOP FLANGE
2 8 %"
*-—Intermediate diaphragm (flfl
----Intermediate diaphragm (flfl
Sole R IO"xfff(fin)xl'-Civ
Shop-driven structural ribbed bolts
SECTION A-A
dip (flfl
End diaphragm
AU stiffener Ls 4"x 4"x ff in pairs.
AU stiffener Ls to bear top and bottom
Protection orq/e --------♦
Sole IO‘xff(fin.)xTO
-Slotted holes iffx iff
A-A below
Girder @ 24 'VETA^x 31' 6-
Laminated wood floor 2'x6’x I4'-O‘, see nailing scheme on sheet no 14-.
Girder @
End diaphragm (flfl
Intermediate diaphragm (flf
Girder (flfl
"Sok R IO\ Wffinjd-O’-
Bearing R
HALF-PLAN ATIbOTTOM FLANGE
Notch floor for traction dip if necessary.
Botts__________
Curb blocks
Protection angle (flfl
Traction
Continue
3 spaces 2
5 spaces S> 27'S'd
Curb (each side) 6"x 6'x /'6'-O~r 16 -0' 1 6 blocks 4"x 6\4'O" J
—Protection angle
-Traction dip (flfl
find diaphragm (flfl
Tl----bearing R. @
Shop-driven strudu ra/ ribbed bolts
59
30-FOOT I-BEAM BRIDGE SECTIONS AND DETAILS
SHEET NO. 3
14'-O'
/do "inside to inside of curd
6-3"
6-3"
Bore /" die. for
Intermediate diaphragm (57)
IQ'-Q
End diaphragm (D; gx-So/e pidte-----1
x Bearing plate(QPj) 3'-4"
&
if.
l-L-a
INTERMEDIATE DIAPHRAGM (dj)
l-Ldid-xfXZ-eP-a
HALF-SECTION B-B
HALF-SECTION C-C
a e ort-mg
!/6holes for anchor
T)
ii" / holes
‘Xi 'I'N
7hd. 3
Bo/t L down for shipment.
TRACTION CLIP
r'tx 1-6"bolt, hex. nut
ANCHOR BOLT (Si}
i?. /2 'x | (f/'n) x/-o"
* ।
<$> 0 0
PLAN AT BOTTOM FLANGE
NOTE: USE 33/f6 BOLTS ON SIDES OF SPLICE WHERE FILL PLATES ARE REQUIRED. WHEN NO FILL PLATES ARE REQUIRED, USE 33/jg BOLTS ON ONE SIDE OF SPLICE AND PLACE WASHERS UNDER NUTS.
BOLT DETAILS OF GIRDER SPLICE
STRUCTURAL RIBBED BOLTS
CONNECTION GRIP (INCHES) LENGTH
SPLICE, GIRDER, TOP FLANGE I31/" z32 33/" '16
SPLICE, GIRDER, BOTTOM FLANGE 3“
l3,/32“ 33/16“
SPLICE, GIRDER, WEB I13/" '32 2 %"
DIAPHRAGM, END, TO GIRDER WEB 27/ “ / 32 2 '4
DIAPHRAGM, INTERMEDIATE, TO GIRDER WEB 27/ " /32 1 / " 2 / c /|6
CLIP, TRACTION, TO GIRDER, TOP FLANGE 1 7/ “ 1 /32 zx;
ALL BOLTS ?8“DIAMETER
NOTE: One M.B.M. equals one thousand board feet.
62
60-F00T I-BEAM BRIDGE half-plan and half-section
SHEET NO. 6
Notch floor at opposite end for traction dip if necessary.
t A
Bearing
Symmetrical about
to'o"
to'-o'
IQ'-Q'
See Detail x on sheet no. 7.
End diaphragm (flfl)—
Symmetrical about
center tine of bridge
9"
12'-6%"
Traction dip
Protection angle
2' 50 d cement-coated nails per sq.ft.
Protection an 0'e (flfl
Traction Clip @
of span except as shown __________60'-Q" c to c, bearings
-Wearing surface
Slotted hole_flfl'x2'fl' hole
-Girder flzfl) only ~(g) only *
Lateral (fz)
Lateral (fl)
RIVET AND BOLT SYMBOLS
GIRDER
End diaphragm flfl
SECTION A-A
GIRDER
GIRDER
'a
Material in splice included in weights of girders (szffipndfl
— Intermediate diaphragm (flfl)
22s 20"x3/8"x2'-5"
3" dig hole Girder flfl) only
Intermediate stiffens
(End stiffener /l 4"x4"x3/g',girder(
(215 4"x 4 "x3/g. all girders 2lS4"x4"x3/g,girder
Traction dip @—
Lateral flfl)
Sole 2 IO"x3/4"(fin)xl'~O"
Botts ___ \93/4 2'/4
Curb blocks
—Laminated" wood floor 2"x6"x 14" see nailing scheme on sheet no. 4-.
Girder (g) 33"
VW 132 x IB'-l7/fl' Lateral (flfl
HALF-PLAN AT
TOP FLANGE
Lateral (fl)
Girder flfl) 33"VE !32*x Id'-lCg'
Provide t fill 2 //(£'> '/fix2'-6" I fill 2 H'/fx3/^ x 2~ 6" per splice to be used in field if necessary.
Intermediate diaphragm (flfl
Girder flfl)
Lateral (fl)
33" HE 132*x 25'-!3/4"
Intermediate diaphragm (flfl)
Girder (flfl) 33" VW !32*n 25'-t3/4“
Intermediate diaphragm (flfl)
Girder (2) 33" VW 132*x Id'-lT/B"
Slotted holes l3/,gXl3/4" (both ends)
-Z
Girder (flfl) 33" kW 132 *x 25'-/3/4 "
HALF-PLAN AT BOTTOM FLANGE
c
NOTE)-FOR BOLTING DETAILS SEE SHEET N0.5.
f , (6"x6"x I8‘-O"+I8‘-O"+B‘-O"tl8'-O") . ..
Curb (/2 biocks 4')6"x4‘-Q " ) eoch s,de
2! spa 2'-7- 55'~lf/fl
2'-5'/fl
U spa s' -3 -- 5 7 ‘-9
Slotted hole I'/4"x 2 fl'
Girder flfi only 3"dio hole ।
Girder flfl) only j
Slotted hojgt'/fl'x 2'fl' Girder fe") only
3"dig hole
I' Girder (flfl) only
Shop rivet -2 full heads.
Shop rivet - countersunk and chipped far side.
Shop structural ribbed button head bolt.
Open hole for structural ribbed buttonhead field bolt.
Open hole for structural ribbed c's'k. head field bolt near side
Open hole for structural ribbed c's'k. head field bolt far side.
Slotted hole I'/fxS'/g Girder (flfl) only
Intermediate diaphragm flfl
63
64
GO-FOOT I-BEAM BRIDGE sections and details SHEET NO. 7
*----------------------------—------■ &——---------------------------—-------u,______________________________________________________3'-4" c fo c. girders_
. 9'' .__________________/so" / n si de to /ns/de- of curbs 9" ’ ZX______________2'~ !0"__________, y*
-----------------------------------------------6~3____________ b Girder-----\
—M——; _____
/-3" r 1 — "t '' ________|f-------P
, | fXX ; |Q 0 Z'-^t-a. 1
See sheet no. 4- for details of f/oor. — H Bore /“f for ZjX I
curb bo/t A Xx 0X XX
yy 421 s\®'w JVz
H H k , P
—------------------------------------------- £ c
. ~ ~ = - —---— 4B-XZ- J 'Rmg fill
--------------------------- -.. __r^~ __ ~X’ — g-~c \V-g'c tt-----------X e*----------— --------v jl xr'x ydr \x\ «
ft LW:i zwF \xv
if <4 u * Sy/*1 <
4 pp WWrifV-W^W—z wz^ \Wl
Snddmphrngm@fi----- X^X ।til ill -----------kZ^X>t <-
Wk J______________________________________________________L
-----A—.1 T R| T I x_I__X । T 1 I---------1 / o
y^y^So/e p/a/e ^ULL -------------Ua I
^Beor/ny plate '-----------------------Intermediate diaphragm (^3) INTERMEDIATE______DIAPHRAGM (Da)
3L4" t-8" US" S-4"
__________________ _______/O:O"______________ _
HALF-SECTION B~B HALF-SECTION C-C
l, _____________3'~4 “c. to c. girders
l"(f>xB'-/0"rod,2-hexnuts _____________3'~!"______u
.„, -,, ,_., , - , plfistd. turnbuckle 7 Girder 2'-IO" | 14"
/—' ,, '
„ I \—y ---------- \ y 1 7 ▼
. 74 j Bearing -*^r —----------------------------------------------------------1
I I t t2 18"u 42.7*x3'-t"
/—Girder Position of splice for shipping ।——/
lr± •, Il r III ri 1—X ,0\/
"r=i=s X rg, r~\ ■■ /
|l J 'Girder or (Gp) | - — 2-Rs ZO'xfxZ'S’ P iBZZ
Zx X0 x
, !----- 2-Rs. 5"x IgxS- Ofiy >* xj "R. ///z J x2F n-p
— Bolt L down for shipment. R./2"xg'x3-ofi Rllfixf"x2'-G" !2 6"x J-"x/-Os" END DIAPHRAGM (D4J
p^s/‘. ? ? P——L. ------------------------ x rJ—X—L,
TRACTION CLIP (£2) |~ fDETAIL X
NOTE: BEARING PLATE (BPi) AND ANCHOR BOLT AEh)
SHIPPING SCHEME FOR GIRDER SPLICE ----------------- ------------------------- W
same os for 30-foot bridge; see sheet no. ^-.
90-FOOT TRUSS BRIDGE BILL OF MATERIAL
SHEET NO. 8
MARK Unit BRIDGE, WITHOUT LUMBER SET STOCK NO. 2OOO-I2O UNIT WEIGHT POUNDS NO. REQ'D TOTAL WEIGHT POUNDS MARK UNIT UNIT WEIGHT POUNDS NO. REQ'D TOTAL WEIGHT POUNDS
U ! R Post, end, sloped 740 2 1,480 5/ Stringer 242 !8 4,356
U I L Post, end, sloped 740 2 1,480 S2 Stringer 278 18 5,004
U 2 Chord section, upper, end 1,227 4 4,908 TOTAL STRUCTURAL STEEL 56,927
U 3 Chord section, upper, center 1,655 2 3,310 Clip, floor 0.7 / 3 30 234
L !R Chord section, lower, end 1,129 / 1,129 Bolt, erection , rough, 3/4"dia. x 2/2", threaded 21/4'\ sq. head,! sq.nut 0.74 650 4 8!
L IL Chord section, lower, end /,/ 29 / 1,129 Bott, structural, ribbed,3/4" dia. x ! /e", buttonhead, / hexagonal nut 0.58 8 40 24
L 2R Chord section, lower, center 1,589 2 3,178 Bolt, structural, ribbed, 3/4 " dia. * / ^/te " buttonhead, / hexagonal nut O.6H 780 477
L2L Chord section, lower, center 1,4 66 2 2,932 Bolt, structural, ribbed ,3/4" dia. x i/8", button head, / hexagonal nut 0.634 310 197
L 3R Chord section, lower, end 1,129 / 1,129 Bolt, structural, ribbed ,3/4" dia. x 2/16", button head , / hexagonal nut 0.657 70 46
L 3L Chord section, lower, end 1,129 / 1,129 Bolt, structural, ribbed,3/4" dia. x 2/4", buttonhead , / hexagonal nut 0.680 370 252
Pl Vertical, web 293 4 1,172 Bolt, structural, ribbed, 3/4 " dia. x 27//6, button head, / hexagonal nut 0.703 350 246
P2 Vertical, web 297 8 2,376 Bolt, structural, ribbed, 3/4 " dia. x 2 3/8", buttonhead , / hexagonal nut 0.726 80 58
P3 Vertical, web 324 4 1,296 Bolt, structural, ribbed, 3/4" dia. x 2^3//6", buttonhead, / hexagonal nut 0.749 2 80 210
W! Diagonal, web 202 8 1,616 Bolt, assembly, guardrail 5.1 186 949
W2 Diagonal, web 283 4 1,132 Spool, bearing 3.7 186 688
W3 Diagonal, web 172 2 344 Washers, cut for 3/4 " dia. bolts 0. Ill 975 108
W4 Diagonal, web 69 2 138 Nails, 50d, cement-coated 0.0625 11,200 700
W5 Diagonal, web 67 2 134 Washer, bevel, upper - chord 0.27 1.70 46
Bl Beam, floor, end 1,093 2 2J86 Washer, bevel, floor - beam 0.21 50 H
B2 Beam, floor, intermediate 1,14 6 8 9,16 8 TOTAL METAL IN BRIDGE SET 61,654
El Bracing, lateral, diagonal 77 9 693 LUMBER" (MUST BE REQUISITIONED SEPARATELY) FT. B.M. EACH GROSS QUANT. NO. REQ'D TOTAL M.B.M. GROSS QUANT.
E2 Bracing, lateral, diagonal 37 9 333 LAMINATED FLOOR SYSTEM
E3 Bracing, lateral, diagonal 4 6 9 414 Lumber, rough, 2"x 6"x 14'” 0" 14 600 8.400
A2 Angle, protection 52 4 208 Lumber, rough, 2"x 12"x I6‘~0" 32 60 1.920
A3 Guardrail 24! 18 4,338 Lumber, rough, 2"x 12"x lO'-iO" 24 12 0.288
BP 2 Plate, bearing 43 4 172 TOTAL LUMBER 10.608
AB! Bolt, anchor 4.3 10 43 NOTE: One M.B.M. equals one thousand board feet.
65
66
90-FOOT TRUSS BRIDGE elevation and part plans SHEET NO. 9
------------------------------------------------------------J. ..^1—.........................i----j_____
V VX/X*X 4»!..................V 'V V_V VkiX-^XFX^XXXV V c \zxuXu^IJ7A7~\7wo7{~'
2-a Lacing - b 2-a 2-a Lacing-b Ra 2-a Lacing-b 2-a 2-a Loci'g-b 2-a
2 iX^w-T'b'n, SECTION THROUGH UPPER CHORD
X ’ Z m CENTER LINE OF SPAN
777 d'in‘ !
XXZ^X 5b‘°
j? /C/z \/|n , , „
7/^ \ tfl-\\----------------------IO_LOffi16______________J___________________IQ'-O '46______________1___________________tO'-Q X /•*/ ' \ XX ' /£,"X\ ZZ
^7 7 X ZZM I ? XX X- '? I < »/ X7 I ? XXx “ i % zX
x* X z § % zXX ^X * i /z/ i »" 'X^$X z-x i i
/ / / Zxx xXys ^"XX \ 7 //7 i * \XX® § ?
X,.’*'\o% z XX\A i '■> 'o'Kzz \ «i® z nXXX i ■» s? zkzz. »® i
i XX z7®'' । ^Xz X? i ®Xi XX\ * i?
t X ZZv i. w? Xz X‘ J ' XX’ i XXX ? i 5 X.
> '-FiH RBflrfl'rl'-lfl NSonly-^ 7/ Z' til * * * "®X\ ' P< §■ 7^7 fTf *’>5 ^X zVz T ! S-05' 6 ^^TzTi ^x\
'S X 7^77// :T: sK XX zftX 77 M *** X XX X Xx,
7 x $3-? x$x/i:4—XX)/ z* us x. xx. xfhjx x7x xt
■ - : >\XL“^*Xr TZlI 2-lnsideSplR5"Zi6>2'-0lZ2' X'X-O—XX tH x ’ ; T I —------------------------------------ rn -----------------। i',! । pj A I-----—______________________________f ■ f | *________________________Z I Z^zi? ! tfr '____2-Sol.ts 5 *^/i'e*l-ll'/2 Inside
“ S “X * -----***-------------* ,. „ l^wi ---------444----- t t 444 -- 444. --------J
--If (Ur) 2-156 *4 xfl't IB'-l“ 2-15 6"*6“* fl"*27'-2 fl XX 4* Ship Xted to (0
-7XXa"e' \X«74z ® ELEVATION
■ \ Ship bolted to sole 2.
2L 6“*4"k fl*O'-B"-*!
/ Bearing , „
EXPANSION END ------------------—------------------------ ------------------------------------------ -----------—______'-91°" 'O'-Q O' 0"
c XX " ' fX X~t~*X " Xi x^Xk .'»»***; Z4>j- -yup- XX-X jx~ -Xlx*~
.XMX .;X\ kXL ~ LXJ4X X X~ LjfcX X dX OJ tXXX^ \ rn^\ Batten 2 8">^*t,-5,‘-y 2 _ \ / Bat 2-^ । / I / Vi----------------------F \-----------'------rX X--------------2A—L 1 ~~ ---------------"7 < \ _________ X fl_______T
\ 2 27"r5Zfl'r2'-9fl‘ flff tSpt 212 fl*5Zfl'*t'S"—' Z Z4- » - Bat R-y ~ jZ -f—f. ‘—BatR-y-A \ z—/ Spin gi'X^'x t‘-H fl‘F.S.
\ 2\\ /7 /\X Sh.p bolted ta 0. / 1-LotR-* \ / t-Lat.2-*\ / i-Lat R-, \
\ ©Vf»X 77/ / \ hL°' P- Z3"x5/I6iZ'-3"-* / \ / \ / \
\ 7/7 / X PLAN OF LOWER CHORD 7 7 X
n n/ / ( Truss
j. \ /Z / I"
5 Slotted holes \ Z-vX //6 / ., \ ..
S. fyg*2fl' this \z°, /zv” / I, 7 J- 7 -\
l> endonlylJrigVholes ,'-^, ^-yX ///X » /
■5 at fixed end \l \S’» <*W *>\V
Z Ji T blXX 77 r------r~r
» ■-T'ELii*— \X //'X / Bearing ki1 L
* — - ------ >- ________r-B" _____. V
\ --'Za» ' Z - Jt Shop rivet• countersunk and chipped near side. , , i " ,«
\ / I * xf-6 rod-f-hex nut a.IO'xfl
\ / / \ --Open hole for structural ribbed button head field bolt. , . , .
/// \X— (Eg) LS'/X'* fl* a'-3 fl /-Z z~^ (fin)xl-e
7/ ^77 41 ________________________________ ANCHOR BOLT (ABi) BEARING PLATE BPa)
—Bott to sole R for shipment.
90-FOOT TRUSS BRIDGE FLOOR SYSTEM AND BRACING
SHEET NO. 10
(^bearing
9O'~0" c. to c. bearings
about jf of bridge Notch floor at opposite end
2-50-d cement- coated for traction clip ifnecessary,
nails per sq. ft except in
outside plank.—
10'-0"
10'-0
Wearing surface (alternate
3'3'3
PART PLAN OF FLOOR
/ 50" inside to inside of guardrails.
i-6-50d cement-coated nails per sq. ft. in outside plank only.
—Laminated wood floor 2"x6'x I4'-O‘> see nailing scheme on' sheet nd. tz.
6'~3"~
„ H——Counterbore 3" x3"
Guardrail Qq)~\ 5^" deep for bearing spool.
\ Bore l"t for guardrail bolt
Symmetrical of bridge Guardrail bolt~\^\x^
HP RfTT fffl SECTION A-A
ffl m ।
® ®\ |
। — --- , *T^III il^
@ - .___________________ 3'-/0"
RIVET AND BOLT SYMBOLS
Shop rivet - 2 full heads.
Shop rivet - countersunk and chipped near side.
Shop rivet - countersunk and chipped far side.
Shop structural ribbed buttonhead bolt.
Open hole for structural ribbed buttonhead field bolt.
Open hole for structural ribbedc's'k head field bolt, near side.
Open hole for structural ribbed c's'k head field bo/t, far side.
bl
90-FOOT TRUSS BRIDGE floor beams and stringers
SHEET NO. 11
l5'-9s" b.tob. dip /s b.
fl stringer
■4?
QJ
Z'-Qfd
2-OFe
3'-10
4-0
/5-8$"b. to b Ls
. 15 « £1^
Block bottom flge. of floor beam .15 "
A
^63*x/5-7/"
______________ 3'-!0
L6\6'x^x8"-b
.<0 O
INTERMEDIATE FLOOR BEAM (B2
No/e :
All shop rivets in floor beams and stringers / V except as noted.
Al I open holes
AH edge distances except es shown.
68
69
90-FOOT TRUSS BRIDGE flooring and guardrail details SHEET NO. 12
Symmetrical, about t of floor
4- I ' "■ Board A h _____________________ _ // 2?
•Jr -- — -----------------------------------------Board B § > : L ■ < ■ ; ?: j Z~- - /'
•$----- ■■ - " —Board c A---- jU- 'U ........~ ■ ---Board X • X| £-
’&=-----------—------------------------ Board A e P : : ; : zz=zzz^zzz--z—zzz=zc ■.----—zzc -
PI AN x—Board B T 1 ! ’H ■■ f■ -. : ■ ■ ■ i , _ , , . ~i i---------------- —1~tx r*
L_hAN etc A---i -"jji ■ J' -. .;. . . ,.j; -—-Board Y \
co' ' ; I —— ZL._............. ■■ Vr Hn
—....—.. u? -■ 7 *—Board x m------------
/-5" T
_ ' coated noils. ----£2--------£]--------R-”~-------Bp--
fop of laminations___________________|_____________________ I [ J---L-------------------
- - - —-r^z' m ~ ~ fE. 4"*8 x'5“
t-----£, . .t, ।-------—~ I^J __±J ELEVATION BOARD X
ELEVATION BOARD B ’
z-/ /- , , 4 FLOOR CLIP
Clips fastened with 50 d cement- coated nails.-' ------------
q'1 l~Q,t l~f)" I'6" II" 5" 5" ___________________________V.__________। Galvanize after
r *’ d— -r — r [- -t q ---£]--------&=------------------------1 fabrication.
Top of laminations\ ; |
------1-------ELEVATION BOARD Y
ELEVATION BOARD C
NAILING SCHEME FOR FLOOR CLIPS ,i^ .
------------------------------------//6 / cored ho/e
NAILING SCHEME FOR LAMINATED FLOOR ___________________________________________________________________________________ _________5-/0"__________________ //S5'=\\ J
g" -■- 2" 3!a)/-0"=3-0" 9". g" I Hi ZZVAl
/O'-Q" B L5"x3px^ x5‘-!0 1-4 b holes
.... ___..... 9'd/f' $ PROTECTION ANGLE (A2) " 3\ Z.------- ...2’-O".......________________3 5/oa./5) 2-0"=6'-0"___ __________2'-Q" ....L, ._ ............7______________' —is_______. - =4 " O if
: i; !: t| 11 i ।
L i; ■■ ,4 !i ■ a H/prdf ____l
(A*-—"I-------------^--‘1--^— -------------- d 4*—------------------------^——ffJ
'—L 8"xG"x/x9'-H^ B| // \
ELEVATION f 0 \ 4 \ BEARING SPOOL
\ I \ Cash- Iron, class 20
\ x .rm
r-r-t......- t—..............................................
r L/C 't holes w///hf/7X7////////Z:\ ____ -— Bearing s/ooo/
c -------------n------\■——————।r---------- 545 heavy lock washer
stiffeners only n(jj.
SECTION A-A SECTION B~B K<
GUARDRAIL (Q) GUARDRAIL BOLT
70
90-F00T TRUSS BRIDGE bolting diagram SHEET NO. 13
r—-f—i
......-t .-...A ......t..---------------------------ty jL,♦./■?,>< At ---»------.........................I___'J__£
- 1 lv v v v v 1 ' + ' r v w x/ w rfHf IY x/ x/ v TJ- | 1 rY7-szzr7-r7-VT^
B J W X ,F
B \< _»-♦ - ♦♦♦] -XX xy XX 't -fbf * ■ - ■
-yy zfex ... ■..-=i.2£=~-h--- ij j,_ -TkljJyn.
£•—t PSP! Ti >2y 4+ \ \f 4 [/ XX y-/Spl/t2T^6",l'-llyFS.
Xr I / PLAN OF LOWER CHORD ' 7
©k # I STRUCTURAL RIVET SIZES
\\ // RIBBED BOLTS SHOWN THUS
% /© B0LT inGcRhes|l^h ._____________.
\\ // —----------------------------- A i5/32 lX H—-1 * 4 ^-i
rr-j^------X. # .,t_-,__-Z RIVET AND BOLT SYMBOLS ~g-----2^~~fiy [____x_____J^
IT ~ % xf C 27/32 iy
y\ //7 '—E - ' U- Shop rive!-2 full heads. D | l/32 2I/|6 I X 1
~ Sh°P r Vef C0unfer5un* ond ch'PPe<^ near s'^e • E '7/32 | 2 j 11 ।
5 " ' - i——(h Open hole for structural ribbed button head field boll. F lTj2 2^/|g' --T—
//f^X A -L-L . g px? ALL BOLTS INCLUDED
/// \\ (Ez) j --77---P25X-9|3/ ■■ BETWEEN EXTENDED
# --- - । ' 32 „2 16 CENTER LINES TO BE
-^X-L_ J4-L- , ALL BOLTS 3/4 DIA. SIZE SHOWN.
ERECTION OF 90-FOOT TRUSS BRIDGE assembly and erection diagrams SHEET NO. 14
CENTER LINE OF SPAN
. -_ "T®1 ■ -n- - L--a ...........-.......... 1 r;"'j " " T \..........................................................................................................n rn /zfn rn (W).// rn—ma
//H X । 12 // । । 26 X i // i \ 20 Z> AVx
€?.Z i Xk i X i W. i X Xfl i zZ i X I '
7// ! X/ : ■ (pz) y--] 25 '! 67 ZZ ' x\ ’ Z~Z XX ■
// : B-Z PP>X : /'/T\ I ZZ \\ : X X\ I /'Xx i V3/ PP$X I >6 Zz(Wi) I X ) XX
// t 5 ® \x 4 zz® i 67 \\ 4 // t /X® T /7 4- //i4 4 i3 \\
c/ r\ i 6 \x i zz 10 \. r\ 77 \\ 1 z® 4 // o n i 18 \\ t zz pp i m
—-X (lir) .«. \X QJ Z/ □ (L2R) " \\ |_Ll // \fy xZ X> ill X (*-29 □ \\ 111 ZZ (L3l) 1 \
E/ m= rm 2 W 24 m V 7—z ,=> 4 m ng
’ "1 I ‘... .i . • ----- I I------••-.Z---J"........... " p---------------------------! I I ■■ ■ , ’
EXPANSION END I_____________________________________9 j PANELS @ IO1 - 0" = 9O'-Q"___________________________________________________________________FlXED END
— ~ ~ I________________________ I ! I ------------------------------------------------------------------------------pp i I '
______,------------------------ CAMBER BLOCKING -------------- ,__________
5/16" 77 25/32” 1 25/32"
TRUSS ASSEMBLY DIAGRAM
NOTE: NUMBERS UNDER THE CIRCLES INDICATE
|-------f-!----------------T-t--1--------j--- ■ 1- I' / l-'lim ;---- 1 r--i ~ (-, CONSECUTIVE ORDER FOR PLACING MEMBERS
I .... I............... I m 1 111 j~ "II | j ~ — zM T WHEN TRUSSES ARE assembled and
[ I_________________________| _ |-L _ I, . I 7~j ~T - _______"j__________JZ ____ LAUNCHED SEPARATELY AND FLOOR IS
|^n®STRUCTURALRIBBEDB0LJT^ ® ® ® 0 /FTP ' ■ “^ELS SH°WN ”ESF0R
t = = = = = = r% = = = = = = = = = = = = = = = = = = = y== = T== = XxC =. j| FLOOR BEAM OFFSET
r yv———————-ft X X-----------------------------------------rt V -----~7=N-------f ~tt---U|| APPROXIMATELY ONE-
\\ // 1 \\ \\ // II \ // 11 HALF INCH AT ONE END
\\(eJ) panel 1 Zm P| \\(e3) pan.eI- 2 //(X ll x V? PANEL 3 / /Ye7 ? J?r^Lp°Rr PLACING 0F
i v pp /: W //- //V :
1 z ® / / ! \ ® // ! :
t---------P?P PA____________________________P______/? //________A ?5 I XP I
||r^- --------------------' — — =f F= — — = — — 1 411= == = = = == ^= = = = =/=/ = = = = = = ^:^lfe;=s = = 1= = = =4^f =1p== = It =j^|l|
, —TP-----------------------70-/—t*----------\\---tt'—————--^< rQ II
11 , W // /Z 11 /C\ W // 11 iro) ££ \\ / *
II VW/ v II \®2) Wx//ALL CONNECTIONS 'P 2B \p^^.\ / H PP
ALL CONNECTIONS P/\ ERECTION BOLTS || 2 v/\ MADE WITH —► [] iO ■' 'N/r/' \ FLOOR ERECTION DIAGRAM
MADE WITH ZU PP K //A ERECTION BOLTS. 11 " X 7/d, \ " 11 !8 ~
H STRUCTURAL ® \\ H ZU // W ' H /7 V\ Wl'. (ENLARGED)
II RIBBED BOLTS.// W ® \\ H VP // W II / p // \\P
l ---------------------X-—w 0_____________,5 -//-_-w____________a // N23 ' j!
ip ZZ W----7— s W: ^ — = = === = =/ff _ = = = ^x= = = = = = =eL Jj|^: j^Z=X= = = = //= = = p\=L d :=^|
if 7/ W \ T 7/ W-----------------------------------------------------------77-----------WZ"^-----1,1
11 // w (E2) \ 11 // \\ m h // 11
11 7/ W 5 \ ! // W A3 II // 'X?'' W (W !
// (si) W \ II // m W !! m W*7 " NOTE: THE METHOD FOR PLACING STRINGERS
// 72 \\ HI // \\ P7 P W " SHOWN IN PANEL 3 APPLIES TO ALL PANELS.
>1 77 6 W \ # 14 W 22 W "
ik-.B- = ------------- - - -k - ,4,XP--------------- ---P\ --^1
IF // —- XV y 77--------------------------Y’^TZ----------------------------1 NOTE: AFTER STRINGERS IN PANEL 3
'If--/® W-'4—~// (L2l) Wp_JJ HAVE BEEN PLACED AND CONNECTED
A STRUCTURAL RIBBED BOLTsW ! V ___W J! FW !. W1TH ERECTION BOLTS, ALL CONNECTIONS
Tl | I ......... I -------------—-------------T-T------/ !' ifTx""1 rTl --------------Y=T nh IN PANEL I ARE MADE WITH STRUCTURAL
■ I" F f" ---------;----------7 j " p [ ------—t---- -j~ -------p LM "j'--- RIBBED BOLTS. THIS PROCEDURE IS TO
r-L- P__________________________JL_____________________t _ 1 7 _ ___| _;______________ BE FOLLOWED IN ALL SUBSEQUENT
1-------। — I I. I ! !-..... xi.ipp’L-; L j L J L T1! pan els.
71
ERECTION OF 90-FOOT TRUSS BRIDGE complete-bridge assembly diagram SHEET NO. 15
CENTER LINE OF SPAN
T . ' ~ I . . l ... ZZJ F=X ' ------- 7'
77) ° rn ® z>rn <\ rn ® Xn z> na ®
X/^rn i 29 7/ ! vX ' 54 /7 /7 * 'Z® 72 zZ^^xX
zz^ : • <-> 7/ ' ^\x 77) ’ // ■ i 7/ ■
7/ i Xk i® /. L\ i® w » i(R) Z I X X // i v<
Z/ I I® ■ X z/ i (® ^xK • 36 )—k ' 51 z/ ' ZL x\ ' Zz~- ' Co\ 'xK
z/ i« gx i 7® t28 7, i / \ i 7 tv ®x i “ 7® X \\
7 © i a 7 1/" te v \ ffl /© 7 ffl 7 a © I 60 7 7 al x
q 7F Ld <—z—A 24 X-—zz 49 4^ z—> Xy X® < y, =-Z 1 <37
-J I_____U ;_________ ‘J I I____________^4 _____ I V C~~—,__( 1 _______47___________C X < 1 68
7 ■ — 1 ' ' - ■• ■ ' - . I EZ ' L~_.. ' - - 1 J ■ f xh
EXPANSION END_________________ _____________I___________9 | PANELS @ 10' - 0" = 90'-0"________ FIXED END
[ | I _________________ ’ ’
I _u___ __________ ~~ CAMBER BLOCKING ‘ ------------------
W ^7' 25^7 Ztf 25/32" 19/32" ” ’ 7' '
FAR TRUSS
I bearing
mt Ji— ! • <7! ! ! 1 X ' ■ ! - !—i i- !- |' ^3' 1 I 11 !i i 1 ii ii in) X 11 11 11 i-ijlx
S : ® I ® i ® I ® i®Z i®\@ Z i®\V Z i®\® Z i®X Z i
E i ‘ I 7 । ,s I 20 i 31 //© z \ X -i « \ Z i « \ Z i " \ Z i
2 i® ® i® ® i(£) ® i(£) ® I® ®V /O. i ® \\/ (eV ® Z / iX ® Z Z (ZI © Z 7 i
o it v * x " v “ X ®i v y ®i w y j y © y
■Li ® I ® । ® i ® ®A ®/x । WZ \ i(x Z \ iWZW
i 5 । ‘° i ,e । " I X @\ ; V/ @\ ■ V/ (X I VZ \ i \ ।
,; K---; B ; r .........4 i H—-. . - :: I ; I &// \ Ing/ ^7 I,,, / @\ \^// (X i,
H ® Cl) LI ® ' + ® 4- G) ® 1 ® \ 1&2 (G) \i®/ \ I®/ :X/© \ I
■iFZ^ 4 Vi—I ।—। 17 —X i* X /st/ Xx ® X
^7+ 11 " Xu ii [j j..............j ii ij. LJ LJ [j □ Lj n X h i । ”h +ZM
HALF-PLAN — STRINGERS AND FLOOR BEAMS c=l HALF-PLAN — LATERALS ANO FLOOR BEAMS i'//®"1
zn 'L □ z-> in1- ' ' -—ir~t=F' •
zZ-> nr ® z>m<\ Pl<\® Zm zsFlSc n ® FX
77 v i 7 i x i \ 71 z । V । ^ xW
®z7 i X Lx i®X I X/§ i / I®/ U 7 \ \x®
z/ i® @y /7 ®z z\ ।7 7) \33 i® z® i® ^Xx
fz ! 25 XX 1 /7 27 ; 35 x\ ! zz7 7. T Zz 32 > \X 1 7/ 69 I \X
m e u X yz m @ \uz& @\j/ ® i \i / e। v
T " X dO ■ 24 Vi, =>_________ VH HT
N0TE !RECL^DXflMZPBE7sSFOR%^)LMFPNLyES NEAR TRUSS N0TE THE NUMBERS SH0WN UNDER THE CIRCLES 'N““TE the consecutive order for placing
ARE BOLTED TO MEMBERS FOR SHIPMENT. ----------- MEMBERS WHEN THE ENTIRE BRIDGE IS ASSEMBLED PRIOR TO LAUNCHING.
72
ERECTION OF 90-FOOT TRUSS BRIDGE launching scheme for assembled bridge
SHEET NO. 16
Bridge as erected
NOTE: When bridge has been moved to a position with the ends directly above their respective bearing plates, jack up structure to release load on timber bent. Remove cribbing and jack-down bridge to final position on bearing plates.
8"x6"x20'-0
39-0
6-0
6'~0
45-0
90'~0" C.toC. Bearings
Anchor timber skid to ground
Level ground as required for bottom of bent.
2"x 12" Planks.
Move planks ahead as bridge is moved forward.
NOTE: SEE SHEET NO. 17 FOR ADDITIONAL DETAILS.
39-0
45-0"
to both sides.
-1____
3/4" Wire rope guy to both sides.
3/4" Wire rope guy
Falls for moving bridge 3 Parts - 5/q" wire rope.
NOTE! Erect bridge in position shown above. Erect all steel bridge members at this time. Do not place timber floor and guard rails until bridge has been moved ahead and jacked-down to final position on bearing plates.
3/4bolt
Bevel corners of block ^F/nor beam
Guide block Clamping block
TYPICAL ERECTION PROCEDURE FOR ASSEMBLED SO'-Q" TRUSS SPAN
l6'-6"C.toC. Trusses
NOTE: Guide blocks are required at the first five pane! points only.
Bolt - to bear against edge of lateral 2. 2"x4“Clamping block
2"x8"xl'~4" Guide block-
i'-io’X
12'-8" OS. to OS. Bent
!2'~ 9 '/g INS, to INS. Guide blocks
!6'-6"C.toC. Trusses
and horizontal timber bracing between frames.
VIEW B-B
Floor beam
Guide block
Guide block
CONNECTION OF GUIDE BLOCKS TO BOTTOM LATERAL PLATES
SCHEME FOR ERECTING
TIMBER BENT
73
ERECTION OF 90-F00T TRUSS BRIDGE details for launching assembled bridge
SHEET NO. 17
12-8"OS. to OS. !2'-Q" C to C
I2'-O"C.to C
4'-0
4-0
4'~0
ms
-.ft
8x8 x/4 ~O
^-8"xl2"x/6'-0
XSo/f
Guy
-2x8
y-2x8
2‘x8“ timber scab - one side
Bo/t-Ufi
2x8
2x8
8x8
bottom of floor beams
Yd
JWAVWVJ!'
Anchor skid beams to ground
Bearing
2x8
TIMBER SKID AT ABUTMENT
^-Timber Sills
Spike 2"x8" timbers to the 8"x8" skid beams.
-Blocking as required
Elevation __________ ______
during erection of bridge
Countersink bolt heads below surface of / timber skid.
p- Grease top of timbers.
2x8-]
SPECIAL NOTE
Top of timber bent cap to be below bearing plate.
2"x8
8"x8"x 14'-0‘
-------Q__
fiA-2"x8" under 8"x8 /4'-O"
/2‘-O‘
Grease top of timbers
Eleva!ion - top of bearing 2
TYPICAL DETAIL OF TIMBER BENT
NOTES FOR TIMBER BENT
The center support can be built without cribbing. In that case it will be removed by sawing trestle supporting members and pulling the trestle down.
Height of bent and number of panels will vary to suit field conditions.
Slope of diagonal bracing to be approx. 12 :!2. Vary slightly as required.
Unbraced length of 8"x8"bent legs is not to exceed !4'-O".
Frame bottom of bent so a
6"x8" clamping timber 8"x8"x20'~O" timber-Bolt
1
— T
SECTION A-A
2"x 12" Planks
Round off bottom edges l'-9" Approximately
minimum amount of excavation will be required to level timber sills.
BLOCKING AT END OF TRUSS
74
TYPICAL MULTIPLE-SPAN BRIDGE
SHEET NO. 18
Y 04
ELEVATION-PI ER
5 x 12 x 24 -0
6"xl6"xl7'-0
6"xl6"x 24-0
3-4'
3-0"
BEARING t
l"
,62_____t BEARING
l°f
DETAIL AT JUNCTION OF 60-AND 90-F00T SPANS
DETAIL AT JUNCTION OF 90'AND 30-F00T SPANS
75
Bolts Paragraph 13c, 16e, 19d Page 4, 5 7 Sheet 1-13 Capacity Posted _ _ .. .
INDEX Bracing: Diagonal, lateral (90-foot bridge) Lateral (60-foot bridge) Bracing, splices, fasteners: 30-foot bridge: Bolts and nuts Diaphragms _ 54c 41 Table Center line of bridge, location Clearance
48b 24
13c 13b 4 4 1 2, 3 Completion of bridge: 30-foot bridge: Installation of curb Installation of floor Setting girders Wearing surface and protection angles 60-foot bridge: Installation of floor Lateral bracing Setting girders 90-foot bridge: Construction of floor
Parts 13a 4
Abutments: Anchor bolts Bearing plates Composition and issue _ Footings, elevations of _ _ __ General _ .. . . Paragraph 34b Page 14 Sheet 60-foot bridge: Bolts and nuts Diagonal lateral bracing Diaphragms Parts Splices 13, 16e 16c 4, 5
34c 14 4, 5 5 5 5
7c 3 16b 16a 16d 6, 7
32c 11
10a 3
10b 3
34d 14 90-foot bridge: Composition and issue:
Repair Sills 1 68a 47 Bolts and nuts 19d 7 1-13 Bridges
34a 14 Bracing 19b 7 9, 10 Erection equipment., j
Parts 19a 7 Piers and abutments Connecting bar Construction, pier, multiple-span Construction surveys:
28b 11
Alternate methods of launching: Splices Bridge, 30-foot I-beam Assembly of steel Bracings, splices, fasteners Completion 19c la 7 1 8-13
30-foot bridge _ _ _ 42c 23 41 21
60-foot bridge Anchor bolts, position of 47d 24 13 43 4 23 1-13
12d. 15d. 18d. 34b. 32e 4, 5, 7, 14, 11 4 Accuracy Center line of bearing plates Elevation of abutment footings General Location of center line Position of anchor bolts Curb installation
Description Floor system General Launching 12, 13, 14 14 40 42 4
Angle, protection: 30- and 60-foot bridge 90-foot, bridve 14d 4 19 21 4 1-4
20c 8 Main girder and end bearings. _ Removal 12 4 2
Assemblv of bridve launching- assembled bridve 56 41 15 44 23
Assembly of equipment: General Bridge, 60-foot I-beam Assembly of girder la 1 Design, basis of:
29a 46 24 Bearings
1 1 Connections Curb
Maintenance Storage 29c 29b 11 Bracings, splices, fasteners 13, 16 4, 5 4-7
11 Completion 43b, 48 23, 24
Floor
Description Floor system General Launching Main girder and end bearings Removal 15, 16, 17 14, 17 40c, 45 37, 47 12, 15 49 5
Assembly of material: Blocking for shipment.. General . 30b 11 4, 5 21, 23 16, 24 4, 5 24 4 4-7 Loading Material
_ 25, 30a 9. 11 Working stresses _ _
Storage Assembly of steel: General: Final bolting Precautions Preliminary bolting _ _ 30-foot bridge 60-foot bridge: Double girder Position of sections 30c 11 6 Diagonal lateral bracing Diaphragms: 30-foot bridge 60-foot bridge
Bridge, 90-foot truss Assembly of truss la 1
36b 52 29
15
36c 36a 16 Bracings, splices, fasteners 19 7 1-13 Dimensions
Description 18, 19, 20 6, 7, 8
15 Drawings: 30-foot bridge 60-foot bridge
41 21 Erection 51 29 8-13
Floor system Launching truss 20, 54 53 8, 40 29 10-12
46b 24 90-foot bridge ’ Driftpins
46c 24 Main trusses and end bearings 18 6 9
Single girder Splicing girders 90-foot bridge: Aids 46a 24 Methods of erection 50 49
46d 24 Bridge seat, construction 63c 42 18 End bearings:
51c 29 Bridges: Composition and issue 1, 5. 8 30-foot. bridge: Anchor bolt
Assembly of truss Assembly of bridge . _ _ Construction of floor _ 52 29 7a 3 End bearings
56 41 Factors affecting exact location: Parts
Approach and access roads 23b 8 60-foot bridge:
54 40
Clearance 23d 9 Anchor bolts
Bearing plates: 34c 14 Foundations 23? 9 End bearings Parts
Center line of 32d 11 General 23a 8
Blocks, steel 37c 16 Length of bridge 23c 9 90-foot bridge: Anchor bolts End bearings Parts
Bolting, steel members: Final 36b 15 Scheme of erection _ Plans, estimates, schedules . _ Site, preparation of 23/, 25 25 9 9 1, 5, 8
Preliminary 36a 15 26, 28c 9, 11
Paragraph Page Sheet
4 3 4, 12
4a 3
4b 3
326 11
6 3
43c 23
436 23 4
43a 23
43d 23
436, 48c 23, 24
486 24
48a 24
54 40
7a 3 1, 5, 8
76 3
7c 3
35/ 15
63 42 18
32/ 11
32e 11
32c 11
32a 11
326 11
32e 11
43c 23
11/ 3
11(7 3
lid 3
lie 3
Ila 3
116 3
11c 3
16c 5
136 4 2, 3
166 5 6, 7
5 3
40a 19 1-4
45a 23 4-7
51a 29 8-13
35a 15
12d 4
12c 4
12a 4
12d, 15d 4, 5
12c, 15c 4, 5
15a 5
18d 7
18c 7
18a 6
76
F Equipment, assembly of: Paragraph Page Sheet Floor Continued. General 29a 11 “Telegraphing” beams and sn>. Maintenance 29c 11 Wearing surface and protecq j a+riT.QOO 29b 11 Installation: JJ . Paragraph Page Sheet Launching single truss: rs 54b 41 Assembly of truss: Paragraph Page Sheet Igle 54/ 41 Equipment 52a 29
„ . 7/, Q 3 30-foot bridge I Eauipment erection: - o o . Order of placing truss members 52c 29 14
1 X: J A, /inh 10 60-foot bridge I 30-foot bridge 40b 19 .. . , , . , aw 23 90-foot bridge 60-foot bridge 400 -I 90-foot bridge 50c 29 Floor system. ■n x- nn c x i j 30-foot bridge: Erection, 90-foot bridge: „ Assembly of steel 51c 29 . Assignment of tasks 51b 29 Flooring _ _ 43b 23 4 Preliminary preparations 52b 29 14 _ 43b, 48c 23, 24 Launching truss: । 43b, 54e 23,41 12 Floating 53/ 40 From position parallel to bank 53c 40 , General 53^ 29 14e 4 Gin pole and crane _. 53b 30
2 \ r1n on o_|9 Parts Drawings ’ 51a 29 » L<5 Protection angle Erection, methods. Traction clip . General 60-foot bridge (see 30-foot bridge 90-foot bridge: 90-foot bridge: Factors -- Floor beams " Equipment 50c 29 Flooring General - Guardrail Erection tools, special (see also table VIII): Parts ” Connecting bar 1 35/ 15 Protection angle Driftpins 35a 15 Stringers _ 14a 4 Two gin poles ___ 53d 30
; 14d 4 Layout of piers. _ _ _ 63a 42 18
14c 4
30-foot bridge:
20a 8 Parts 12a 4 20e 8 60-foot bridge:
Ratchet chain hoist 35c 15 Shackles 35b 15 Slines 35e 15 4 . End bearings 12c, 15c 4, 5 6 Girders 15b 5 Parts 15a 5
OK J -IK nUJUOlUlCHV Ml Spud wrench f climbing 37d 16 90-foot bridge:
Estimates, bridge: Use in launching: Bills of material . 25c 9 1, 5, 8 With crane 37e 16 Anchor bolts _ _ I8d 7
End bearings 18c 7
Equipment 25e 9 With tractor 37, 47b, 53b 16, 24, 30 Main trusses 18b 6 9 47c 24 Parts _ . _ 18a 5
53c 30 Maintenance, repairs and strengthening:
Work quantities 25b 9 __ Assembly: Expansion and contraction, provision for 34d 14 Double girder Maintenance 67 47 Repairs 68 47
I osition of sections__ J 46b 24 Strengthening. . 69 47
46c 24 Manual, scope of 11
Fasteners, splices, bracings: Single girder 30-foot bridge: Splicing girders J Bolts and nuts 13c 4 1 30-foot bridge ' Diaphragms 13b 4 2,3 Setting of girders - Parts 13a 4 60-foot bridge 60-foot bridge: Setting of girders Bolts and nuts 16c 5 4, 5 Guardrail installation
43a 23 General 25,30a 9,11
.... 20/, 54^ 8,41 Packaging of 5 3
Diaphragms 16b 5 6, 7 pflr+s 16a 5 _ , rarts__ Labor Splices 16s 5 4, o 90-foot bridge: Launehmg «Med bndge: Bolts and nuts IM 7 1,13 Assembly of bridge.-. Bracing . 1% 7 9,10 By floating: Parts — — IM 7 Prehmmary.. „ io- 7 8-18 Procedure Splices 19c t x. From bank: Floating: . Launching assembled bridge 58 42 Y Launching bv floating single truss 53/ 40 Multiple span: Floor construction 65 42 18 8 3 _ General ... . 62 42
Launching method 64 42 56 41 15 Pier construction 63 42 18
58a 42 Ordering:
_ _ 58b 42 Equipment _ 27c 10
Lumber 27b 10 57a 41 __ Other material _ 27d 10
Launching methods _ 64c 42 ’ kk n .. .• ...
ploor. Launching, 30-foot bridge: °°Beams 54a 40 14 Alternate methods.. V71^cLI14Z