STANDARD SPECIFICATIONS FOR CONSTRUCTION OF ROADS AND BRIDGES ON FEDERAL HIGHWAY PROJECTS (FP-14) - page 12

 

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STANDARD SPECIFICATIONS FOR CONSTRUCTION OF ROADS AND BRIDGES ON FEDERAL HIGHWAY PROJECTS (FP-14) - page 12

 

 

Section 553
Show inlet and outlet locations on drawings.
Provide positive mechanical shut-off valves for inlets and outlets. Provide inlets and outlets with
valves, caps, or other devices capable of withstanding the grouting pressure.
Securely fasten ducts in place to prevent movement. Maintain distances from the forms by stays,
blocks, ties, hangers, or other approved supports. Use precast mortar blocks of approved shape and
dimensions. Separate layers of ducts by mortar blocks.
Space duct supports according to the PTI, Guide Specification for Grouting of Post-Tensioned
Structures. Cover the ends of ducts to prevent the entry of water or debris.
Connect inlets and outlets to the duct with metallic or plastic structural fasteners. Do not use
components that react with the concrete, cause corrosion of the prestressing steel, or contain water
soluble chlorides.
(b) Placing concrete. Where the end of a post-tensioned assembly will not be covered by concrete,
recess the anchoring devices so that the ends of the prestressing steel and all parts of the anchoring
devices are at least 2 inches (50 millimeters) inside the end surface of the members.
Before placing concrete, demonstrate that ducts are unobstructed. Immediately after concrete
placement, blow out the metal conduit with compressed, oil-free air to break-up and remove mortar in
the conduit before it hardens. Approximately 24 hours after the concrete placement, flush the metal
conduits with water containing lime (calcium oxide) or slaked lime (calcium hydroxide) in the quantity
of 0.1 pounds per gallon (12 grams per liter). Blow the water out with compressed, oil-free air.
For post-tensioned members that are to be steam cured, do not install prestressing steel until curing is
complete.
(c) Anchorages and distribution. Give at least 10 days notice before installing end fittings or heading
wires.
When wires are used, provide an edge distance for any hole for prestressing wire through a stressing
washer, unthreaded bearing ring, or plate of at least ¼ inch (6 millimeters) from the root of any threads
or the edge of any ring, plate, or washer.
Anchor post-tensioned prestressing steel at the ends by permanent type anchoring devices capable of
developing not less than 95 percent of the ultimate tensile strength of the prestressing steel. If the
anchoring device is sufficiently large and is used in conjunction with a steel grillage embedded in the
concrete that effectively distributes the anchor load to the concrete, the steel distribution plates or
assemblies may be omitted.
Enclose loop tendon anchorages in ducts for their entire length.
(d) Prestressing steel. Use a corrosion inhibitor to protect prestressing steel installed in ducts before
placing and curing of the concrete. Use a corrosion inhibitor that does not adversely affect the steel,
concrete, or bond strength of the steel to concrete.
If prestressing steel is installed in the ducts within 10 days after concrete curing, stressing, and
grouting are completed, no corrosion inhibitor is required.
425
Section 553
(e) Post-tensioning. Wait at least 10 days after the last concrete has been placed in the member or until
tests on concrete cylinders indicate that the concrete has attained the minimum compressive strength.
Demonstrate that the prestressing steel is free and unbonded in the duct. Straighten wires if necessary
to produce equal stress in all wires, wire groups, or parallel lay tendons that are stressed
simultaneously. Remove side forms for girders before post-tensioning.
Record gauge pressures and prestressing steel elongation at all times while tensioning prestressing
steel and submit records.
Determine the friction loss in the prestressing process (that is the difference between tension at the jack
and minimum tension in the prestressing steel) according to the AASHTO, Load and Resistance
Factor Design (LFRD) Bridge Design Specifications.
Use suitable shims or other approved devices to attain the specified anchor set loss.
(f) Grouting. Provide Class A, B, C, or D grout as specified and prestressing steel that is free of dirt,
loose rust, grease, or other deleterious material. Bond post-tensioned prestressing steel to the concrete
by filling the void space between the duct and tendon with grout according to the PTI, Guide
Specification for Grouting of Post-Tensioned Structures.
Perform grouting operations using staff with grouting experience on projects of a similar type and
magnitude. Perform grouting operations under the immediate supervision of an individual skilled in
various aspects of grouting and who is certified by the American Segmental Bridge Institute (ASBI)
Grouting Certification program. Furnish the name of the grouting operations supervisor and proof of
their ASBI certification and grouting experience before beginning grouting operations.
Make available on-site before beginning grouting operations, the required testing equipment for
checking grout workability (flow-cone), temperatures, and other specified tests.
Use grouting equipment capable of continuous operation with little variation of pressure, which also
includes a system for recirculating the grout while actual grouting is not in progress. Use grouting
equipment capable of maintaining a pressure on completely grouted ducts and fitted with a valve that
can be locked off without loss of pressure in the duct.
Provide written certification that ingredients used in the grout meet the ASTM requirements contained
in the PTI, Guide Specification for Grouting of Post-Tensioned Structures. This includes, but is not
limited to, the following:
(1) Cement mill test reports;
(2) Mineral additives test reports;
(3) Chemical admixtures reports; and
(4) Test reports for other ingredients used in the grout.
For prepackaged grouts, provide the manufacturer’s current certified mill test reports for the product.
Do not use compressed air to aid in the pumping of grout.
426
Section 553
Provide grout pumps of a positive displacement type, capable of providing a continuous flow of grout,
and capable of maintaining an outlet pressure of at least 150 pounds per square inch (1 megapascal)
and with a pressure gauge having a full-scale reading of not more than 300 pounds per square inch
(20 megapascals).
Grout only when the efflux time of a grout sample immediately after mixing is between 11 and
30 seconds according to ASTM C939.When hot weather conditions may cause quick setting of the
grout, cool the grout by approved methods, as necessary, to prevent blockages during pumping
operations. When freezing weather conditions are possible during and following placement of grout,
protect the grout from damage by freezing according to the PTI, Guide Specification for Grouting of
Post-Tensioned Structures.
Provide a supply of potable water and standby flushing equipment capable of developing a pumping
pressure of 250 pounds per square inch (1.7 megapascals) and of sufficient capacity to flush out
partially-grouted ducts.
Clean ducts of material that would impair bonding of the grout or interfere with grouting procedures.
Blow out each duct with compressed, oil-free air. Check inlets and outlets for their capacity to accept
injection of grout by blowing compressed, oil-free air through the system and proving each inlet and
outlet in turn.
Pass grout through a screen with ⅛ inch (3 millimeters) maximum clear openings before entering the
grout pump. Open grout vents before the start of grouting. Completely fill the duct by injecting grout
from the lowest end of the tendon in an uphill direction. Pump grout continuously through the duct and
waste at the outlet until no visible slugs of water or air are ejected, and the efflux time of ejected grout
is between 11 and 30 seconds. Maintain a continuous, one-way flow of grout within a grouting stage.
Close outlets in a similar manner one after the other in the direction of the flow. For outlets placed a
short distance downstream from a high point, close that outlet before its associated high point outlet.
Increase the grouting pressure at the injection end to at least
100 pounds per square inch
(0.7 megapascals) and hold for at least 10 seconds. Do not remove or open valves and caps until the
grout has set.
Abrasive blast clean the concrete surface of recessed anchorage assemblies. Fill anchor recesses with
concrete conforming to the requirements for the structure and finish flush.
Remove ends of vents 1 inch (25 millimeters) below the roadway surface after grouting has been
completed. Permanently seal recess areas.
Do not release the falsework under the bottom slab supporting the superstructure until at least 48 hours
after grouting of the post-tension prestressing steel or until the grout strength is obtained.
427
Section 553
Table 553-1
Prestressed Concrete Member Tolerances
Description
Tolerance
Precast Girders With Cast-In-Place Deck(1)
±¼ in/25 ft, ±1 in max.
Length
(±6 mm/10 m, ±25 mm max.)
+⅜ in, -¼ in
Width (overall)
(+10 mm, -6 mm)
+½ in, -¼ in
Depth (overall)
(+13 mm, -6 mm)
-¼ in
Depth (flanges)
(-6 mm)
+⅜ in, -¼ in
Width (web)
(+10 mm, -5 mm)
⅛ in/10 ft
Sweep (2)
(3 mm/3 m)
±316 in/ft, ±1 in max.
Variation from end squareness or skew
(±5 mm/10 m, ±25 mm max.)
Camber variation from design camber
±⅛ in/10 ft
(±3 mm/3 m)
±½ in, max. ≤ 80 ft length
(±13 mm, max. ≤ 25 m length)
±1 in, max. > 80 ft length
(±25 mm, max. > 25 m length)
Position of strands:
Individual
±¼ in (±6 mm)
Bundled
±½ in (±13 mm)
Position from design location of deflection points for
±20 in (±500 mm)
deflected strands
Position of plates other than bearing plates
±1 in (±25 mm)
Position of bearing plates
±⅝ in (±15 mm)
Tipping and flushness of plates
±¼ in (±6 mm)
Tipping and flushness of bearing plates
±⅛ in (±5 mm)
Position of inserts for structural connections
±½ in (±13 mm)
Position of handling devices:
Parallel to length
±6 in (±150 mm)
Transverse to length
±1 in (±25 mm)
Position of stirrups:
Longitudinal spacing
±2 in (±50 mm)
Projection above top
±¾ in (±19 mm)
±¼ in in 10 ft (±6 mm in 3 m)
Local smoothness (3)
any surface
428
Section 553
Table 553-1 (continued)
Prestressed Concrete Member Tolerances
Description
Tolerance
Precast Girders Used In Multi-Beam Decks (4)
Length
±¾ in (±19 mm)
Width (overall)
±¼ in (±6 mm)
Depth (overall)
±¼ in (±6 mm)
Depth (top flange)
±½ in (±13 mm)
+½ in, -18 in
Depth (bottom flange)
(+15 mm, 5 mm))
Width (web)
±⅜ in (±10 mm)
Sweep (5)
Up to 40 ft (12 m) member length
±¼ in (±6 mm)
40 to 60 ft (12 to 18 m) member length
±⅜ in (±10 mm)
Greater than 60 ft (18 m) member length
±½ in (±13 mm)
Variation from end squareness or skew
±⅛ in/ft (±10 mm/m)
Horizontal
±½ in max. (±13 mm max.)
Vertical
±½ in (±13 mm)
±⅛ in/10 ft, ±½ in max.
Camber variation from design camber
(±3 mm/3 m, ±13 mm max.)
Differential camber between adjacent members
¼ in/10 ft, ¾ in max.
of the same design
(±6 mm/3 m, ±20 mm max.)
Position of Strands:
Individual
±¼ in (±6 mm)
Bundled
±¼ in (±6 mm)
Position from design location of deflection points
±20 in (±500 mm)
for deflected strands
Position of plates other than bearing plates
±1 in (±25 mm)
Tipping and flushness of plates
±¼ in (±6 mm)
Position of inserts for structural connections
±½ in (±15 mm)
Position of handling devices:
Parallel to length
±6 in (±150 mm)
Transverse to length
±1 in (±25 mm)
429
Section 553
Table 553-1 (continued)
Prestressed Concrete Member Tolerances
Description
Tolerance
Precast Girders Used In Multi-Beam Decks
Position of stirrups:
Longitudinal spacing
±1 in (±25 mm)
Projection above top
+¼ in, -¾ in (+6 mm, -20 mm)
Tipping of beam seat bearing area
±⅛ in (±5 mm)
Position of dowel tubes
±58 in (±15 mm)
Position of tie rod tubes:
Parallel to length
±½ in (±13 mm)
Vertical
±⅜ in (±10 mm)
Position of slab void:
End of void to center of tie hole
±½ in (±13 mm)
Adjacent to end block
±1 in (±25 mm)
±¼ in in 10 ft (±6 mm in 3 m)
Local smoothness (6)
any surface
Post-Tension Members
Position of post tensioning ducts
±¼ in (±5 mm)
Position of tendon anchorage bearing plates
±¼ in (±5 mm)
(1) AASHTO I Beams and Bulb-T Girders.
(2) Variation from straight line parallel to centerline of member.
(3) Does not apply to top surface left rough to receive a topping or to visually concealed surfaces.
(4) Box beams, slabs, decked bulb tee, and multi-stem girders.
(5) Variation from straight line parallel to centerline of member.
(6) Does not apply to top surface left rough to receive a topping or to visually-concealed surfaces.
553.11 Painting Steel. Use a wire brush or abrasive blast to remove dirt and residue not firmly bonded to
the metal or concrete surfaces. Clean and paint the exposed ends of the prestress steel, post-tension anchor
head assemblies, and a 1-inch (25-millimeter) strip of adjoining concrete.
Mix zinc-rich paint conforming to FSS TT-P-641. Work the paint into voids in the prestressing tendons.
Apply one thick coat to surfaces that will be covered with concrete. Apply two coats to surfaces not
covered with concrete.
553.12 Acceptance. See Tables 552-9 and 553-2 for sampling, testing, and acceptance requirements.
Prestressing steel, reinforcing steel, anchor devices, elastomeric bearings, and material for concrete and
grout will be evaluated under Subsection 106.03. Furnish production certifications with each shipment of
hydraulic cement, prestressing steel, and reinforcing steel.
Grouting will be evaluated under Subsections 106.02 and 106.04. Sampling and testing requirements will
be according to the PTI, Guide Specification for Grouting of Post-Tensioned Structures.
Concrete for precast, prestressed concrete members will be evaluated under Subsections 106.02, 106.03,
and 106.04.
430
Section 553
Concrete for post-tensioned, cast-in-place concrete members will be evaluated under Section 552.
Construction of precast, prestressed concrete members and post-tensioned, cast-in-place concrete members
will be evaluated under Subsections 106.02 and 106.04.
Reinforcing steel will be evaluated under Section 554.
Falsework and forms will be evaluated under Section 562.
Measurement
553.13 Measure the Section 553 pay items listed in the bid schedule according to Subsection 109.02 and
the following as applicable:
Do not measure reinforcing steel and concrete for precast, prestressed concrete structural members.
Measure the concrete for post-tensioned, cast-in-place concrete structures under Section 552.
Measure the reinforcing steel for post-tensioned, cast-in-place concrete structures under Section 554.
Measure prestressed piling under Section 551.
Payment
553.14 The accepted quantities will be paid at the contract price per unit of measurement for the Section
553 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
431
Section 553
Table 553-2
Sampling, Testing, and Acceptance Requirements
Material or
Type of
Characteristic
Category
Test Methods
Sampling
Point of
Split
Reporting
Remarks
Product
Acceptance
Specifications
Frequency
Sampling
Sample
Time
(Subsection)
(Subsection)
Prestressed
Measured and
Compressive
AASHTO
1 per
Discharge
Yes
Upon
concrete
tested for
strength
T 23 & T 22
30 yd³
stream at
completing
conformance
(25 m³)(2)
point of
tests
(106.04)
placing(1)
Grout
"
PTI, Guide
Each
Each
No
"
Specification
mixture
source
for
Grouting of
Post-Tensioned
Structures
(1) Sample according to AASHTO R 60, except composite samples are not required.
(2) In addition to the test cylinders required to determine 28-day strength, cast two release cylinders for each concrete member. Cure the release-strength
cylinders with the concrete member that they represent.
432
Section 554
Section 554. — REINFORCING STEEL
Description
554.01 This work consists of furnishing and placing reinforcing steel.
Material
554.02 Conform to the following Subsection:
Reinforcing steel
709.01
Construction Requirements
554.03 Order Lists. On reinforcing steel order lists, use the same respective bar marks for labeling as
shown in the plans. Submit order lists and bending diagrams for approval. Approval does not relieve the
Contractor of responsibility for the accuracy of the lists and diagrams. Do not order material until the lists
and diagrams are accepted.
Do not fabricate vertical reinforcement in columns, walls, piers, and shafts until footing elevations are
established in the field.
554.04 Identification. Ship bar reinforcement in standard bundles, tagged and marked according to CRSI,
Manual of Standard Practice.
554.05 Bending. Fabricate reinforcing bars according to ACI SP-66, ACI Detailing Manual. Cold bend
reinforcing bars that require bending. Limit the overall height or drop bending tolerance of deck truss bars
to plus 0 inch (0 millimeter) or minus ¼ inch (6 millimeters). Do not bend bars partially embedded in
concrete, except as shown in the plans or otherwise permitted.
Provide standard hooks conforming to ACI SP-66.
554.06 Protection of Material. Store reinforcing steel above the ground on platforms, skids, or other
supports. Protect from physical damage, rust, and other surface deterioration.
Use reinforcing steel only when the surface is clean and the minimum dimensions, cross-sectional area,
and tensile properties conform to the physical requirements for the size and grade of steel specified.
Do not use reinforcing steel that is cracked, laminated, or is covered with dirt, rust, loose scale, paint,
grease, oil, or other deleterious material.
554.07 Epoxy-Coated Reinforcing Steel. Support coated bars on padded contact areas. Pad bundled
bands. Lift with a strong back, multiple supports, or a platform bridge. Prevent bar-to-bar abrasion. Do not
drop or drag bundles.
Before placement, inspect bars for coating damage. Replace and do not use bars with a total damaged area
in any 12-inch (300-millimeter) length that exceeds 5 percent of the surface area of that length of the bar.
433
Section 554
Clean other damaged coatings by removing surface contaminants and the damaged coating. Roughen the
area around the damage and remove rust by blast cleaning or power tool cleaning. Use a prequalified
ASTM A775 patching/repair material to patch defects in the coating that are discernible to the unaided
eye. Overlap the patching material onto the original coating for
2 inches
(50 millimeters) or as
recommended by the manufacturer. Provide a minimum 8 mil (200-micrometer) dry film thickness on the
patched areas.
Take necessary steps to minimize damage to the coating of installed bars. Clean and patch damage to
coatings noted after installation as described above. Promptly treat the bar according to the resin
manufacturer’s recommendations and before detrimental oxidation occurs.
Coat mechanical splices after splice installation according to ASTM A775 for patching damaged epoxy
coatings.
554.08 Placing and Fastening. Place, fasten, and support the bars according to the CRSI, Manual of
Standard Practice. Coat chairs, tie wires, and other devices used to support, position, or fasten
epoxy-coated reinforcement with a dielectric material.
Use precast concrete blocks or metal supports. Attach concrete block supports to the supported bar with
wire cast in the center of each block. Use Class 1 (plastic protected) or Class 2, Type B (stainless steel
protected) metal supports in contact with exposed concrete surfaces. Use stainless steel conforming to
ASTM A493, Type 430.
Space slab bar supports no more than 48 inches (1200 millimeters) apart transversely or longitudinally. Do
not use bar supports either directly or indirectly to support runways for concrete buggies or other similar
construction loads. Replace damaged supports.
Place bars within 1½ inches (38 millimeters) of the plan location. Do not cumulate spacing variations. Do
not allow the average of any two adjacent spaces to exceed the required spacing. Place reinforcing steel in
deck slabs within ¼ inch (6 millimeters) of the vertical plan location. Using a template, check the clear
cover over deck reinforcing steel before placing deck concrete.
Provide 2 inches (50 millimeters) clear cover for reinforcement. The tolerance on minimum concrete cover
is minus ⅜ inch (10 millimeters). For concrete surfaces cast against the ground provide a minimum
3 inches (75 millimeters) of clear cover over reinforcement.
Tie reinforcing at intersections around the perimeter of each mat and at not more than
24-inch
(600-millimeter) centers or at every intersection, whichever is greater. Tie bridge deck reinforcing bars at
not more than 12 inch (300 millimeter) or every intersection, whichever is greater.
Tie bundle bars together at intervals not exceeding 6 feet (1.8 meters). Do not bundle bars unless the
location and splice details are specified.
Do not place concrete in members until the reinforcing steel placement is approved.
554.09 Splices. Splicing, except as shown in the plans, is not permitted without approval. Provide lap
lengths shown in the plans. Splice reinforcing bars only where shown in the plans or accepted drawings.
Make lapped splices by placing the reinforcing bars in contact and wiring them together so as to maintain
the alignment and position of the bars.
434
Section 554
If welding of reinforcing steel is permitted, use welders with current certifications and make the welds
conform to AWS, Structural Welding Code - Reinforcing Steel, D 1.4 (D1.4M). Do not weld reinforcing
steel if the chemical composition of the steel exceeds the percentages in Table 554-1.
Table 554-1
Reinforcing Steel Components
Chemical Composition
Percent
Carbon (C)
0.30
Manganese (MA)
1.50
Carbon Equivalent (C.E.)
0.55
Mechanical couplers may be used instead of welding if approved. Use couplers with a strength that is at
least
125 percent of the required yield strength of the reinforcing steel. Do not exceed 0.01 inches
(0.25 millimeters) total slip of the reinforcing bar within the splice sleeve when loading in tension to
30.0 kips per square inch (207 megapascals) and relaxing to 3.0 kips per square inch (20 megapascals) for
bar sizes up to No. 14 (No. 43) as measured between gage points clear of the splice sleeve.
If welded wire fabric is shipped in rolls, straighten into flat sheets before placing. Splice sheets of mesh or
bar mat reinforcement by overlapping not less than 1-mesh width plus 2 inches (50 millimeters). Securely
fasten at the ends and edges.
554.10 Acceptance. Reinforcing steel and epoxy coating material will be evaluated under Subsections
106.02 and 106.03. Furnish a production certification with each shipment of reinforcing steel.
Placement of reinforcing steel will be evaluated under Subsections 106.02 and 106.04.
Measurement
554.11 Measure the Section 554 pay items listed in the bid schedule according to Subsection 109.02 and
the following as applicable:
Measure reinforcing steel excluding laps added for the Contractor's convenience.
Payment
554.12 The accepted quantities will be paid at the contract price per unit of measurement for the Section
554 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
435
Section 555
Section 555. — STEEL STRUCTURES
Description
555.01 This work consists of constructing steel structures and the steel structure portions of composite
structures. This work also includes furnishing, fabricating, and erecting
structural steel and incidental
metal construction.
Material
555.02 Conform to the following Sections and Subsections:
Bearing devices
564
Bolts and nuts
717.01(d)
Castings
717.04
Galvanized coatings
717.07
High-strength bolts, nuts, and washers
717.01(e)
Painting
563
Pins and rollers
717.03
Preformed polychloroprene elastomeric joint seal for bridges
712.01(g)
Sheet lead
717.08
Steel forgings
717.02
Steel grid floors
717.09
Steel pipe
717.06
Structural steel
717.01
Temporary works
562
Welded stud shear connectors
717.05
Construction Requirements
555.03 Drawings and Diagrams. Submit drawings according to Subsection 104.03.
(a) Fabrication drawings. Show complete detailed dimensions and sizes of component parts of the
structure and details of miscellaneous parts.
Show the direction of plate rolling where specific orientation of plates is required. Show plate girder
flanges and webs cut from plates so the long dimension of the girder parallels the rolling direction.
Identify the type and grade of each piece that is to be made of steel other than AASHTO M 270,
Grade 36 (250) steel.
Show assembly marks that are cross-referenced to the original pieces of mill steel and their certified
mill test reports.
Shop-welded splice locations shown on the drawings are subject to approval. Locate shop-welded
splices to avoid points of maximum tensile or fatigue stress. Locate splices in webs at least 12 inches
(300 millimeters) from shop splices, flange butt joints, or stiffeners. Additional nondestructive tests
may be required on shop-welded splices.
436
Section 555
(b) Erection drawings. Fully illustrate the proposed method of erection. Show details of falsework
bents, bracing, guys, dead-men, lifting devices, and bridge member attachments. Show the erection
sequence, crane and barge locations, crane capacities, lifting point locations, and bridge member
masses. Show complete details for anticipated phases and erection conditions. If required by the CO
during drawing review, provide calculations showing that allowable stresses are not exceeded and that
member capacities and final geometry are correct. See Section 562 for additional requirements.
(c) Camber diagram. Show the camber at each truss or arch rib panel point, at field splice locations,
and at the specified span length fractions of continuous beams and girders or rigid frames. Show
calculated cambers to be used in preassembly of the structure as required in Subsection 555.14.
(d) Transportation drawings. Show support points, tie-downs, temporary stiffening trusses or beams,
and other details needed to support and brace the member. Provide calculation sheets showing
self-weight plus dynamic load allowance stresses induced by the loading and transportation procedure.
Use dynamic load allowance stresses of at least 100 percent of the dead load stress. Do not allow
fatigue stresses to exceed the constant-amplitude fatigue threshold for the appropriate categories.
Verify computed girder stresses satisfy the AASHTO, Load and Resistance Factor Design (LRFD)
Bridge Design Specifications.
Ship and store members in the same orientation as the completed structure unless otherwise approved
by the CO.
555.04 Fabrication Notice. Give written notice at least 21 days before beginning fabrication work. Do
not manufacture material before notification and drawings are approved.
555.05 Inspection. Structural steel may be inspected at the fabrication site according to Subsection
106.06.
Ultrasonically inspect girder flanges before fabrication according to ASTM A578 and the following:
(a) Inspect after flanges are stripped from the master plate;
(b) Use supplementary requirement S2.1 for acceptance standards; and
(c) Inspect flanges in the plant or warehouse where the flanges are stripped.
Furnish copies of mill orders at the time orders are placed with the manufacturer. Furnish certified mill test
reports and production certifications before the start of fabrication using material covered by these reports.
Furnish a production certification from the manufacturer according to Subsection 106.03.
Include on certified mill test reports the chemical analyses and physical test results for each heat of steel
used in the work and for steels with specified impact values, include the results of Charpy V-notch impact
tests. Confirm on the test report that the material was so produced when fine-grain practice is specified.
Furnish production certifications instead of mill test reports for material that is not normally supplied with
mill test reports and for items such as fills, minor gusset plates, and similar material when quantities are
small and the material is taken from stock.
437
Section 555
555.06 Storing Material. Store structural material above the ground on platforms, skids, or other
supports. Keep material without dirt, grease, and other foreign matter. Protection from corrosion and stray
electrical currents.
555.07 Fabrication. Fabricate structural steel in a fabricating plant that is certified under the AISC,
Quality Certification Program. Furnish and fabricate fracture critical elements according to AASHTO,
LRFD Bridge Design Specifications and Clause 12 of the AASHTO/AWS, Bridge Welding Code D1.5
(D1.5M).
Remove mill scale and foreign material from exterior surfaces of exterior girders of unpainted
weathering steel by blast cleaning according to SSPC-SP6, Commercial Blast Cleaning. Then dry the
surface and apply at least three uniform applications of water mist at 24 hour intervals to ensure uniform
weathering.
Do not heat curved steel girders.
Do not drill, cut, or weld portions of structural members unless shown in the plans or approved in writing.
(a) Steel identification. Use a system of assembly-marking of individual pieces and cutting
instructions (generally by cross referencing of the assembly-marks shown on the drawings with the
corresponding item covered on the mill purchase order). Provide information to the shop that maintains
the identity of the original piece.
Identify material furnished from stock by heat number and mill test report.
During fabrication and before assembling members, show the specification of each piece of steel (other
than Grade 36 (250) steel). Mark steel using steel die stamping or firmly attaching a substantial tag to
pieces of steel which will be subject to fabricating operations which might obliterate paint marking
before assembling into members. These fabrication operations include blast cleaning, galvanizing,
heating for forming, or painting.
Use low-stress type steel die stamps. Avoid impressions near edges of tensile-stressed plate members.
Do not use die stamps on fracture-critical members.
Furnish an affidavit certifying the identification of steel has been maintained throughout the fabrication
operation.
(b) Plates.
(1) Rolling direction. Cut and fabricate steel plates for main members and splice plates for
flanges and main tension members, so that the primary direction of rolling is parallel to the
direction of the principal tensile and compressive stresses.
(2) Plate cut edges.
(a) Edge planing. Remove sheared edges on plates thicker than 58 inches (15 millimeters) to
a depth of ¼ inch (6 millimeters) beyond the original sheared edge or beyond re-entrant cuts
produced by shearing. Fillet re-entrant cuts before cutting.
(1) Oxygen cutting. Perform oxygen cutting according to AASHTO/AWS, Bridge
Welding Code D1.5 (D1.5M).
438
Section 555
(2) Visual inspection and repair of plate cut edges. Visually inspect and repair plate cut
edges. Conform to AASHTO/AWS, Bridge Welding Code D1.5 (D1.5M).
(b) Flange plates. Furnish flange plates with either oxygen-cut edges that have ground
corners chamfered at least 116 inch (1.6 millimeters) or furnish universal mill plates.
(c) Web plates. Use oxygen cutting to provide the prescribed camber in web plates of built-up
beams and girders, box girders, and box arches. Cut sufficient extra camber into the webs to
provide for camber losses due to welding and cutting.
(d) Truss members. Prepare longitudinal edges of plates in welded sections of truss web and
chord members by oxygen cutting. Use grinding to chamfer the edges of the corners of plates
at least 116 inch (1.6 millimeters) when plates are not joined by welding.
(e) Stiffeners and connection plates. Sheared edges may be used on plate thicknesses up to
¾ inches (19 millimeters) for stiffeners and connection plates welded transverse to girder
webs and flanges. Universal mill plate may be used for plate thicknesses up to 1 inch
(25 millimeters). Furnish other stiffeners and connection plates with oxygen-cut edges.
(f) Lateral gusset plates. Bolted lateral gusset plates may be furnished with sheared edges
provided the thickness is less than or equal to ¾ inches (19 millimeters). Oxygen cut, parallel
to lines of stress, gusset plates and other connections welded parallel to lines of stress in
tension members where the plate thickness exceeds ⅜ inches (10 millimeters).
(g) Splice plates and gusset plates. Furnish with oxygen-cut edges.
(h) Bent plates. Furnish un-welded, load-carrying, rolled steel plates.
Bend plates at right angles to the direction of rolling, except cold-bent ribs for
orthotropic-deck bridges may be bent in the direction of rolling.
Before bending, round the plate corners to a radius of 116 inch (1.6 millimeters) throughout
the portion of the plate where the bending occurs.
(1) Cold bending. Do not cold-bend fracture-critical steels and fracture-critical members.
For other steels and members, cold bend according to Table 555-1 so that no plate
cracking occurs. Allow for springback of Grades 100 (690) and 100W (690W) steels
equal to about three times that for Grade 36 (250) steel. Use a lower die span of at least
sixteen times the plate thickness for break press forming.
(2) Hot bending. If a radius shorter than the minimum specified for cold bending is
required; hot bend the plates at a temperature less than 1,200 °F (650 °C), except for
Grades 70W (485W), 100 (690) and 100W (690W). When steel plates are heated to
temperatures greater than
1,100 °F
(595 °C) for Grade 100 (690) and Grade 100W
(690W) or greater than 1,050 °F (565 °C) for Grade 70W (485W); re-quench and temper
according to the producing mill's standard practice and test to verify restoration of
specified properties. Do not heat Grade HPS 70W (HPS 485W) to a temperature greater
than 1,100 °F (595 °C). Re-quenching and tempering is not required for Grade HPS 70W
(HPS 485W) steel heated to this limit.
439
Section 555
Table 555-1
Minimum Cold-Bending Radii(1)
Grade,
Thickness, (t)
kips per square inch
t ≤ ¾ inch
¾ inch < t ≤ 1 inch
1 inch < t ≤ 2 inches
t > 2 inches
(megapascals)
(t ≤ 20 mm)
(20 mm < t ≤ 25 mm)
(25 mm < t ≤ 50 mm)
(t > 50 mm)
36 (250)
1.5t
1.5t
1.5t
2.0t
50 (345), 50S (345S),
50W (345W), or
1.5t
1.5t
2.0t
2.5t
HPS 50W (HPS 345W)
HPS 70W (HPS 485W)
1.5t
1.5t
2.5t
3.0t
100 (690)
1.75t
2.25t
4.5t
5.5t
100W (690W)
1.75t
2.25t
4.5t
5.5t
(1) Values shown are for the concave face of the metal bent perpendicular to the direction of final rolling. If the bend is
parallel to the direction of final rolling, multiply the minimum radii shown by 1.5 (that is 1.5t perpendicular to rolling
equates to 2.25t parallel to rolling).
(c) Stiffener fit. Fabricate (mill, grind, or weld) girder end bearing stiffeners and concentrated load
bearing stiffeners to provide full bearing on the flanges to which the load is transmitted or received.
Fabricate intermediate stiffeners to provide a tight fit against the compression flange.
(d) Abutting joints. Mill or saw cut abutting joints in truss and column compression members to
obtain a square joint and uniform bearing. Other joints not required to be faced may have openings up
to ⅜ inch (10 millimeters).
(e) Bearing surface facing. Finish bearing surfaces according to Table 555-2 and ASME, B46.1
Surface Roughness, Waviness and Lay, Part I.
Table 555-2
ASME Surface Roughness Values
Surface
Bearing Surface
Roughness Value
µin (µm)
Steel slabs
2,000 (50)
Heavy plates in contact in shoes to be welded
1,000 (25)
Milled ends of compression members, milled or
500 (13)
ground ends of stiffeners and fillers
Bridge rollers and rockers
250 (6)
Pins and pin holes
125 (3)
Sliding bearings
125 (3)
Machine sliding bearings with a surface roughness greater than 75 micro-inches (2 micrometers) so the
lay of the cut is parallel to the direction of movement.
440
Section 555
Fabricate bearing parts to provide uniform even contact with the adjacent bearing surface. Limit the
maximum gap between bearing surfaces to 0.04 inches (1 millimeter). Machine the base plate sliding
surfaces if the plane and true base and sole plates exceed the surface roughness value of Table 555-2.
Do not machine surfaces of fabricated assemblies until heat treatment and fabrication on the assembly
is complete.
(f) Straightening material. Straighten plates, angles, other shapes, and built-up members using
methods that do not fracture or damage the metal when approved by the CO.
Use mechanical means or a limited amount of localized heat when approved by the CO. Do not exceed
the temperatures shown in Table 555-3 and control the heat application with temperature-indicating
crayons, liquids, or bimetal thermometers. Remove external forces from the material to be
straightened, except for the mechanical stress designed to be used in conjunction with the heat.
Table 555-3
Maximum Straightening Temperatures
Material to be Straightened
Maximum Temperature
Grade HPS 1100W (Grade HPS 690W)
1100 °F (595 °C)
Grade 100W (Grade 690W)
1100 °F (590 °C)
Other Steels
1200 °F (650 °C)
555.08 Annealing and Stress Relieving. Normalize and anneal (full annealing) according to ASTM
A941. Maintain uniform temperatures throughout the furnace during the heating and cooling so the
temperature at no two points on the member differs by more than 100 °F (55 °C).
Record each furnace charge, identify the pieces in the charge, and show the temperatures and schedule
used. Provide proper instruments including recording pyrometers for determining member temperatures.
Provide records of the treatment operation for approval.
Do not anneal or normalize HPS 100W (HPS 690W) or HPS 70W (HPS 485W) steel members without
approval. See Table 555-3 for the maximum stress relieving holding temperature for these grades.
Stress relieve members (such as bridge shoes, pedestals, or other parts that are built-up by welding sections
of plate together) according to Subsection 4.4 of AASHTO/AWS, Bridge Welding Code D1.5 (D1.5M).
555.09 Bolt Holes. Punch or drill bolt holes. If required below, either subpunch or subdrill holes 316 inch
(5 millimeters) smaller than the nominal bolt diameter and after assembling ream or drill full size.
(a) Punched holes. Unless subpunching and reaming is required by Subsection 555.09(h); punch
material forming parts of a member with no more than 5 metal thicknesses if the material thickness is
no greater than:
(1) ¾ inch (19 millimeters) for structural steel;
(2) ⅝ inch (15 millimeters) for high-strength steel; or
(3) ½ inch (13 millimeters) for quenched and tempered alloy steel.
441
Section 555
Punch holes 116 inch (1.6 millimeters) larger than the nominal bolt diameter. Ream holes that require
enlarging to admit bolts. Produce clean cut holes without torn or ragged edges.
(b) Reamed or drilled holes. Subdrill and ream or drill holes full-size where there are more than five
thicknesses or where the main material is thicker than Subsection 555.09(a)(1) thru (3).
Assemble and securely hold together connecting parts that are being reamed or drilled and match-mark
before disassembling. Where practical, use twist drills, twist reamers, or roto-broach cutters directed
by mechanical means. Ream or drill cylindrical holes 116 inch (1.6 millimeters) larger than the nominal
bolt diameter that are perpendicular to the member. Remove burrs on the outside surfaces.
(c) Accuracy of holes. Drilled or reamed holes may be up to 132 inch (0.8 millimeter) larger than the
true decimal equivalent of the nominal diameter of the drill or reamer. Punched holes may be slightly
conical. Slotted holes produced by flame-cutting or a combination of drilling, or punching and flame
cutting may be up to 132 inch (0.8 millimeter) larger than the nominal width. Grind flame cut surfaces
smooth to a maximum surface roughness of 1000 micro-inches (25 micrometers).
(d) Accuracy of hole group before reaming. Punch, subpunch, or subdrill holes to allow a cylindrical
pin 316 inch (5 millimeters) smaller in diameter than the nominal size of the punched hole can be
inserted in holes after assembling (before reaming). In addition, produce at least 75 percent of the
contiguous holes in the same plane such that a cylindrical pin ⅛ inch (3 millimeters) smaller in
diameter than the nominal size of the punched hole can be inserted perpendicular to the face of the
member without drifting.
(e) Accuracy of hole group after reaming. Use dimensioned steel templates with hardened steel
bushings in the holes. Use connection centerlines when locating templates from the milled or scribed
ends of members. Produce at least 85 percent of the holes in a contiguous group of holes with a
maximum offset of 132 inch (0.8 millimeter) between adjacent thicknesses of metal after reaming or
drilling.
(f) Numerically-controlled drilled field connections. Drill or punch full-sized bolt holes in
unassembled pieces and connections using numerically-controlled drilling or punching equipment.
(g) Holes for ribbed bolts, turned bolts, or other approved bearing-type bolts. Provide finished
holes with a driving fit.
(h) Preparation of field connections. Drill full size holes through all thicknesses of material
assembled in proper position for field connections and field splices. Do not punch full-size holes in
longitudinal main load-carrying members, transverse floor beams, or components designated as
fracture critical members. Other options include the following:
(1) Main members of trusses, arches, continuous beam spans, bents, towers (each face), plate
girders, and rigid frame connections and splice holes. Subpunch or subdrill and ream while
assembled, or drill full size to a steel template.
(2) Rolled beam stringers continuous over floor beams or cross frames. Drill full-size holes for
field splices unassembled to a steel template.
(3) Floor beam and stringer field end connection holes. Subpunch and ream while assembled, or
drill full size to a steel template.
442
Section 555
(4) Cross frames, lateral bracing components, and the corresponding holes in connection
plates between girders and cross frames or lateral components. Punch full-size holes.
Locate, position, and firmly bolt the template in place when reaming or drilling full size
field-connection holes through a steel template. Use duplicates of templates used for reaming matching
members or the opposite faces of a single member. Locate templates used for connections on like parts
or members so that the parts or members are duplicates and require no match-marking.
555.10 Pins and Rollers.
(a) Fabricating pins and rollers. Fabricate straight and smooth pins and rollers without flaws.
Forge and anneal pins and rollers or use cold-finished carbon steel shafting for diameters less than
9 inches (230 millimeters). Slowly cool forged pins to a temperature below the critical range to prevent
damage from rapid cooling. Bore a hole in the pin not less than 2 inches (50 millimeters) in diameter
full-length along the pin axis before annealing.
(b) Boring pin holes. Do not exceed the pin diameter by more than 150 inch (0.50 millimeters) for pins
5 inches (130 millimeters) or less in diameter or exceed by more than 132 inch (0.8 millimeter) for
larger pins when boring pin holes. Bore pin holes smooth, straight, at right angles with the axis of the
member, and parallel with each other. Produce the final surface using a finishing cut.
Produce a maximum variation in the distance outside-to-outside of end holes in tension members and
inside-to-inside of end holes in compression members of 132 inch (0.8 millimeter) from that specified.
Bore pin holes in built-up members after the member is assembled.
(c) Threads for bolts and pins. Conform to the ASME, B1.1 Unified Inch Screw Threads (UN and
UNR Thread Form), Class 2A for external threads and Class 2B for internal threads (ASME, B1.13M
Metric Screw Threads: M Profile, tolerance Class 6G for external threads and Class 6H for internal
threads). Provide six threads per inch (25 millimeters) for pin ends with a diameter of 1⅜ inches
(35 millimeters) or greater.
555.11 Eyebars. Provide eyebars that are straight and without twists. Limit the inclination of bars to the
plane of the truss to a 0.5 percent slope.
Locate pin holes on the centerline of the eyebar. Securely clamp eyebars that are to be placed side-by-side
in the structure in the order they are to be placed on the pin. Bore the pin holes to the finished diameter
from both ends or flame cut the pin holes at least 2 inches (50 millimeters) smaller than the finished pin
diameter.
Simultaneously cut the edges of eyebars that lie between the transverse centerline of their pin holes with
two mechanically-operated torches abreast of each other guided by a substantial template to prevent
distortion of the plates.
Use low-stress type steel die stamps to match-mark eyebars for shipment and erection. Locate stamps on
the visible edge each member when the bars are nested in place on the structure.
555.12 Assembly-Bolting. Clean metal contact surfaces. Assemble, securely pin, and draw together
member parts. Drill, ream, and bolt the assembly. If necessary, take assembly apart to remove burrs and
shavings produced by the operation.
443
Section 555
Assemble the members without twists, bends, and other deformation. Drift only enough to bring the parts
into position without enlarging holes or distorting metal.
555.13 Welded Connections. Conform to AASHTO/AWS, Bridge Welding Code D1.5 (D1.5M). Install
shear connector studs according to Chapter 7. Perform preproduction testing according to Subsection 7.7.1
and inspect installed studs according to Subsection 7.8.
555.14 Preassembly of Field Connections. Submit method and details of preassembly for approval.
Preassemble field connections of truss, arch, continuous beam, plate girder, bent, tower, and rigid frame
main members. Use preassembly methods and details consistent with approved erection procedures and
camber diagrams.
Assemble girders and beams in their cambered (no load) condition. When members are assembled with
webs vertical, support the members at intervals of 20 feet (6 meters), or two-tenths of the span length,
whichever is less. When the webs are horizontal, support intervals may be increased provided there is no
noticeable deflection between points of support.
Assemble trusses in full dead-load position unless the design of the structure provides for secondary
stresses created by the fully cambered assembly. Start assembly from a location in the structure and
proceed in one or both directions. Support trusses at each panel point. Preassemble at least
three contiguous panels. For successive assemblies, include at least one section or panel of the previous
assembly plus two or more sections or panels added at the advancing end. For structures longer than
150 feet (45 meters), make each assembly at least 150 feet (45 meters) long.
Verify the geometry of the completed structure or unit. Verify or prepare field splices.
(a) Bolted connections. Where applicable, assemble major components with milled ends of
compression members in full bearing. While assembled, ream subsized holes to the specified size.
(b) Check assembly/numerically-controlled drilling. Make a check assembly for each major
structural type of each project based on proposed order of erection, joints in bearings, special complex
points, or similar considerations. Assemble at least three contiguous shop sections. For trusses,
assemble members in at least three contiguous panels, but not less than the number of panels
associated with three contiguous chord lengths (such as the length between field splices). Other shop
assemblies are not required.
Obtain approval of each assembly before reaming holes or dismantling the assembly. Inaccurate
camber, alignment, hole alignment, milled joint fit, or other problems may require additional check
assemblies.
(c) Field-welded connections. Do not field weld connections unless specifically shown on the
drawings. Verify the fit of members (including the proper space between abutting flanges) with the
segment preassembled.
(d) Match marking. Match mark connecting parts preassembled in the shop to ensure proper fit in the
field. Provide a diagram showing match-marks.
444
Section 555
555.15 Connections Using Unfinished, Turned, or Ribbed Bolts. Use bolts conforming to ASTM A307,
Grade A with single self-locking nuts or double nuts. Use beveled washers where bearing faces have a
slope more than 1:20 with respect to a plane normal to the bolt axis.
(a) Turned bolts. Furnish hex headed bolts of the nominal size specified with a body surface ANSI
roughness less than 125 micro-inches (3 micrometers). Ream holes to provide for a light driving fit.
Keep bolt threads outside of the holes. Provide a washer under the hexagonal nut.
(b) Ribbed bolts. Furnish round headed bolts conforming to ASME, B18.5 Round Head Bolts (Inch
Series)
(ASME, B18.5.2.2M Bolts, Metric Round Head Short Square Neck) with continuous
longitudinal ribs. Provide a body diameter measured on a circle through the points of the ribs 564 inch
(2 millimeters) greater than the nominal diameter specified for the bolts. Furnish hexagonal nuts that
are either recessed or have a washer of suitable thickness.
Ream holes to provide for a driving fit. Ream the hole and provide an oversized replacement bolt if the
ribs compress or deform allowing the bolt to twist before drawing tight.
555.16 Connections Using High-Strength Bolts.
(a) Bolted parts. Use only steel material within the grip of the bolt with no compressible material
(such as gaskets or insulation). Fabricate steel parts to fit solidly together after bolts are stressed.
Remove burrs that prevent solid seating. Limit the slope between the bolted surface and the plane
normal to the bolt axis to 1:20.
(b) Surface conditions. Clean dirt, foreign material, and scale (except tight mill scale) from joint
surfaces at the time of assembly. Remove paint (including inadvertent overspray) from areas within the
bolt pattern. In non-coated joints, exclude or remove paint closer than 1 inch (25 millimeters) or one
bolt diameter, whichever is larger, from the edge of holes.
(c) Installation. Use fasteners of the same lot number for each connection. Protect fasteners from dirt
and moisture. Only remove the fasteners from protected storage that are to be installed and tensioned
during a work shift. Return unused fasteners to protected storage at the end of the shift. Do not remove
as-delivered lubricant from fasteners. Discard and replace fasteners for slip-critical connections that
accumulate rust or dirt before installing.
Provide a Skidmore-Wilhelm calibrator or other acceptable bolt tension measuring device. Use the
measuring device to perform the rotational-capacity test and to confirm the following:
Table 555-4 requirement for the complete fastener assembly;
Calibration of the wrenches if applicable; and
Understanding and proper use of the tightening method.
445
Section 555
Table 555-4
Minimum Fastener Tension(1)
ASTM A325
ASTM A490
Nominal Bolt Diameter
pounds
pounds
(Nominal Bolt Diameter and Thread Pitch)
(kilonewtons)
(kilonewtons)
½ inch (M12 × 1.75)
12,000 (49)
15,000 (61)
⅝ inch (M16 × 2)
19,000 (91)
24,000 (114)
¾ inch (M20 × 2.5)
28,000 (142)
35,000 (179)
78 inch (M22 × 2.5)
39,000 (176)
49,000 (221)
1 inch (M24 × 3)
51,000 (205)
64,000 (257)
1⅛ inch (M27 × 3)
56,000 (267)
80,000 (334)
1¼ inch (M30 × 3.5)
71,000 (326)
102,000 (408)
1⅜ inch (M36 × 4)
85,000 (475)
121,000 (595)
(1) Equal to 70 percent of the specified minimum tensile strength of bolts (as specified for tests of
full size ASTM A325 and A490 bolts with UNC threads (metric coarse thread series, ANSI
B1.13M) loaded in axial tension) rounded to the nearest 1,000 pounds (1 kilonewton).
For short grip bolts, perform the calibrated wrench verification test using a direct tension indicator with
solid plates. Check the direct tension indicator with a longer grip bolt in the tension measuring device
before testing short grip bolts. Conform to Subsection 555.16(c)(3) through (6) as applicable for
confirming testing frequency, number of tests, and test procedure. Provide documentation of annual
testing by an approved testing agency confirming the accuracy of the tension measuring device. Install
fasteners with specified washers in properly aligned holes. Tension using methods in Subsection
555.16(c)(3) through (6) to the minimum tension specified in Table 555-4.
When it is impractical to turn the nut, tension the fastener by turning the bolt while preventing the nut
from rotating when approved by the CO. Provide adequate capacity and sufficient air to tension each
bolt in about 10 seconds if impact wrenches are used.
Do not reuse ASTM A490 fasteners and galvanized ASTM A325 fasteners. If approved,
non-galvanized ASTM A325 bolts may be re-used once. Touching up or re-torqueing previously
tensioned bolts (which may have been loosened by the tensioning of adjacent bolts) will not be
considered reuse provided the tensioning continues from the initial position and does not require
greater rotation than that shown in Table 555-5.
446
Section 555
Table 555-5(1)
Nut Rotation from the Snug-Tight Condition(2)
Bolt Length
Geometry of Outer Faces of Bolted Parts
Measured from
Both Faces
One Face Normal to
Both Faces Sloped
Underside of Head
Normal to
Bolt Axis and
Not More Than
to End of Bolt
Bolt Axis
Other Face Sloped
1:20 from Normal
Not More than 1:20
to Bolt Axis
(Bevel Washer Not Used)
(Bevel Washers Not Used)
Up to and including
13 turn
12 turn
23 turn
4 diameters
Over 4 diameters,
but not exceeding
12 turn
23 turn
56 turn
8 diameters
Over 8 diameters,
but not exceeding
23 turn
56 turn
1 turn
12 diameter(3)
(1) Applicable only to connections where all material within the grip of the bolt is steel.
(2) Nut rotation is relative to bolt, regardless of the element (nut or bolt) being turned.
The tolerance is minus 0, plus 30° for bolts installed by one-half turn or less.
The tolerance is minus 0, plus 45° for bolts installed by two-third turn or more.
(3) Determine the required rotation by actual tests in a suitable tension device simulating the actual conditions.
(1) Rotational-capacity tests. Use washers even if not required in the actual installation.
Perform job-site rotational-capacity tests for fastener assemblies according to ASTM A325 and
the following:
(a) Tighten the fastener to a snug-tight condition according to Subsection 555.16(c)(3). Use
the bolt tension measuring device to tighten the fastener two times the required turns shown
in Table 555-5 if impact wrenches are used.
(b) Verify the maximum recorded tension is at least 1.15 times the minimum fastener tension
shown in Table 555-4. Record the tension and torque.
(c) Verify the measured torque at the maximum recorded tension does not exceed the value
obtained by the following equation:
TorqueUSC = 0.25PD
TorqueMetric = 0.34PD
where:
Torque
= Measured torque in foot-pounds (newton-meters)
P
= Maximum recorded tension in pounds (newtons)
D
= Nominal bolt diameter in feet (meters)
(2) Washers. Conform to ASTM F436. Use a hardened beveled washer where the outer face of
the bolted parts has a slope greater than 1:20 with respect to a plane normal to the bolt axis.
447
Section 555
Use hardened square or rectangular beveled washers for American Standard Beams and
Channels.
If necessary, clip washers on one side to within seven-eighths times the bolt diameter measured
from the washer center.
Hardened washers are not required for connections using ASTM A325 and ASTM A490 bolts,
except under the following conditions:
(a) Use a hardened washer under the turned element when the tensioning is done by the
calibrated wrench method.
(b) Use a hardened washer under both the head and the nut when A 490 bolts are installed in
material having a specified yield point less than 40 kips per square inch (275 megapascals).
(c) Use a hardened washer conforming to ASTM F436 where ASTM A325 bolts of any
diameter or ASTM A490 bolts equal to or less than 1-inch (M24) diameter are installed in
oversize or short-slotted holes in an outer ply.
(d) Use
516-inch
(8-millimeter) minimum thickness hardened washers conforming to
ASTM F436 under both the head and the nut instead of standard thickness hardened washers
where ASTM A490 bolts larger than 1-inch (M24) diameter are installed in oversize or short
slotted holes in an outer ply. Do not use multiple hardened washers with a combined
thickness equal to or greater than 516 inch (8 millimeters) to satisfy this requirement.
(e) Use a 516-inch (8-millimeter) minimum thickness plate washer or continuous bar where
ASTM A325 bolts of any diameter or ASTM A490 bolts equal to or less than 1-inch (M24)
diameter are installed in a long-slotted hole in an outer ply. Provide a structural grade steel
bar or plate washer (that need not be hardened) with standard holes and of sufficient size to
cover the slot.
(f) Use a
516-inch
(8-millimeter) minimum thickness hardened washer conforming to
ASTM F436 under both the head and the nut instead of washers or bars of structural grade
material where ASTM A490 bolts larger than 1-inch (M24) diameter are installed in long-
slotted holes in an outer ply. Do not use multiple hardened washers with a combined
thickness equal to or greater than 516 inch (8 millimeters) to satisfy this requirement.
Alternate design fasteners that provide a bearing circle on the head or nut of at least the diameter
of an ASTM F436 hardened washer may be used without washers.
(3) Turn-of-nut installation method. Install bolts in connection holes and pull the plies to firm
contact throughout the connection. Tighten bolts snug-tight beginning with the most rigid part of
the connection and proceeding to the free edges. Verify that plies are in firm contact throughout
the connection.
Apply the rotation shown in Table 555-5 beginning with bolts in most rigid part of the
connection and proceeding to the free edges. Do not allow rotation of the fastener part not turned
by the wrench.
Use a bolt tension-measuring device at the start of work to verify that the tension on at least three
fastener assemblies for each bolt diameter, length, and grade is at least 5 percent greater than the
tension shown in Table 555-4. Periodically test other fastener assemblies when required by the
CO.
448
Section 555
(4) Calibrated wrench installation method. Install bolts with hardened washers under the
turned element and pull the plies to firm contact throughout the connection. Tighten bolts
snug-tight beginning with the most rigid part of the connection and proceeding to the free edges.
Set a calibrated wrench to deliver the torque required to produce a bolt tension at least 5 percent
greater than the tension shown in Table 555-4. Use the calibrated wrench to tension bolts
beginning with the most rigid part of the connection and proceeding to the free edges. Touch up
previously tensioned bolts until bolts are tensioned to the prescribed amount.
Use a bolt tension-measuring devise at least once each shift to verify the tension on the fastener
assemblies installed. Test at least three fastener assemblies of each bolt diameter, length, and
grade installed in that shift. Recalibrate a wrench when the prescribed tension is not achieved or
when a significant difference is noted in the surface condition of the bolts, threads, nuts, or
washers. When tightening from a snug-tight condition, verify that the wrench adjustment
selected by the calibration does not produce a nut or bolt head rotation greater than permitted in
Table 555-5. Torque nuts in the tightening direction when measuring the torque using manual
torque wrenches.
(5) Direct tension indicator (DTI) installation method. Use DTIs conforming to ASTM F959
and installed according to the manufacturer’s recommendations. Position the DTI under the
stationary element or place a hardened washer between the DTI and the turned element.
Install bolts with DTIs and required hardened washers and pull the plies to firm contact
throughout the connection while holding the stationary element against rotation. Remove and
replace all DTIs where the number of spaces in which a 0.005 inches (0.125 millimeters) feeler
gage is refused in the DTI exceeds the number listed in the AASHTO, LRFD Bridge
Construction Specifications table.
For uncoated DTIs used under a stationary or turned element and for coated (galvanized, painted,
or epoxy-coated) DTIs used under a stationary element, further tension the bolts until the number
of refusals of the 0.005 inches (0.125 millimeters) feeler gage is equal to or greater than the
number listed in the AASHTO, LRFD Bridge Construction Specifications table. Remove and
replace bolts that are tensioned so that no visible gap remains. For coated DTIs used under a
turned element, further tension the bolts until all spaces verify that the 0.005 inches (0.125
millimeters) feeler gage shows refusal in all spaces.
Verify the tension in a calibrated bolt-tension measuring device. Use a special flat insert in place
of the normal bolt head holding insert. Perform three verification tests for each combination of
fastener assembly rotational-capacity lot, DTI lot, and DTI position relative to the turned element
(bolt head or nut) to be used on the project. Install the fastener assembly in the
tension-measuring device with the DTI located in the same position as in the work. Restrain the
element intended to be stationary (bolt or nut) from rotation. Conduct verification tests in two
stages according to AASHTO, LRFD Bridge Construction Specifications table.
(6) Alternate design bolt installation method. When approved, furnish alternate fasteners that
meet the material, manufacturing, and chemical composition requirements of ASTM A325 or
ASTM A490 and:
(a) Meet the mechanical property requirements of the same specification in full-size tests,
and
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Section 555
(b) Have body diameter and bearing areas under the head and nut; or their equivalent, not
less than those provided by a bolt and nut of the same nominal dimension.
Install alternate design bolts in connection holes according to the manufacturer’s
recommendations and pull the plies to firm contact throughout the connection. Tighten bolts
snug-tight without yielding or fracturing the control or indicator element of the fastener.
Further tension fasteners beginning with bolts in most rigid part of the connection and
proceeding to the free edges. Proper tensioning of the bolts may require more than a single cycle
of systematic partial tensioning. Replace individual fastener assemblies if yielding or fracture
occurs before the final tensioning cycle.
Verify the tension according to Subsection 555.16(c)(3), (4), or (5).
(7) Inspection. Inspect the tensioned fasteners in the presence of the CO. Replace or re-tension
loose or relaxed fasteners. Cutting with a torch is not permitted for removal of fasteners.
(a) Non-threaded fasteners. Ping each fastener with a hammer to test for soundness.
(b) Threaded fasteners. Use an inspection torque wrench to verify tensioning unless alternate
fasteners or DTI devices are used allowing verification by other methods.
Calibrate the inspection torque wrench at least once each inspection day. Individually place
three fastener assemblies of the same grade, size, and condition as those under inspection in a
device calibrated to measure bolt tension. Use a washer under the part turned in tightening
each bolt if washers are used on the structure. Use the same material that abuts the part
turned in the tension measuring device as used on the structure if washers are not used on the
structure. In the calibration device, tighten each bolt to the specified tension. Apply the
inspecting wrench to the tightened bolt to determine the torque required to turn the nut or
head 5 degrees, approximately 1 inch at a 12-inch (25 millimeters at a 300-millimeter) radius,
in the tightening direction. Use the average of the torque required for all three bolts as the
job-inspection torque.
Randomly select 10 percent (at least two) of the tensioned bolts on the structure in each
connection represented by the test bolts. Apply the job-inspection torque to each selected bolt
with the inspecting wrench turned in the tensioning direction. If this torque turns no bolt head
or nut, the fastener is properly tensioned. If the torque turns one or more bolt heads or nuts,
apply the job-inspection torque to all bolts in the connection. Re-torque and re-inspect
fasteners whose head or nut turns.
555.17 Welding. Conform to AASHTO/AWS, Bridge Welding Code D1.5 (D1.5M) for welding, welder
qualifications, prequalification of weld details, and inspection of welds. For tubular connections, conform
to AWS, Structural Welding Code - Steel, D1.1 (D1.1M) Section 2, Part D.
Do not weld or tack brackets, clips, shipping devices, or other non-required material to members unless
shown on the drawings.
555.18 Erection. Conform to Section 562 for falsework and forms. Use steel erectors certified under the
AISC quality certification program.
(a) Handling and storing material. Place stored material on skids above ground. Keep material clean
and properly drained. Place and shore girders and beams upright. Support long members (such as
columns and chords) on skids placed close enough together to prevent deflection damage.
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Section 555
(b) Bearings and anchorages. Furnish and install bridge bearings according to Section 564. Verify
substructure concrete built under a previous contract was properly constructed before ordering material
for the superstructure.
(c) Erection procedures.
(1) Conformance to drawings. Erect according to approved drawings. Submit revised drawings
and verification of stresses and geometry for modifications to or deviations from the approved
erection procedure for approval.
(2) Erection stresses. Allow for erection stresses locked in the structure as a result of erection
methods or equipment that differ from those previously approved. Provide additional material
necessary to keep both temporary and final stresses within the allowable limits used in the
design.
Provide temporary bracing or stiffening devices to accommodate handling stresses in individual
members or segments.
(3) Maintaining alignment and camber. Support structural segments to produce the proper
alignment and camber in the completed structure. Install cross frames and diagonal bracing
during erection to provide stability and ensure correct geometry. Provide temporary bracing at
any stage of erection.
(d) Field assembly. Clean bearing surfaces and permanent contact surfaces. Assemble material as
shown on the drawings and match-marks. Do not hammer, damage, or distort members.
Assemble splices and field connections with at least half the holes filled with fitting-up bolts and
cylindrical erection pins before installing and tightening the balance of the high-strength bolts. Use
fitting-up bolts that are the same high-strength bolts used in the installation or other bolts of the same
nominal diameter. Use cylindrical erection pins with a diameter 1/32 inch (0.8 millimeter) larger than
the bolts. Fill at least a quarter of the holes with fitting-up bolts and at least another quarter with
erection pins. Place pins in the corner holes of the splice plates. Fill at least three-fourths of the holes
of splices and connections carrying traffic.
Systematically remove fitting-up bolts and cylindrical erection pins and replace them with tightened
high-strength bolts. Start from the most rigid part of connection and proceed to the free edges.
Release temporary erection supports at a splice or connection only after bolts are installed and
tightened. Show special assembly and support situations on the erection drawings.
(e) Pin connections. Use pilot and driving nuts when driving pins. Drive pins so that the members
fully bear on the pins. Screw pin nuts tight and burr the threads at the face of the nut with a pointed
tool.
(f) Misfits. Correct minor misfits using small amounts of reaming, cutting, grinding, and chipping.
Remove and replace members misfit due to shop fabrication error or deformation during handling or
transporting.
555.19 Acceptance. Material (except bearing devices and painting) for steel structures will be evaluated
under Subsections 106.02 and 106.03. Submit a production certification with each shipment of structural
steel, steel forgings, and high-strength bolts, nuts, and washers.
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Section 555
Construction of steel structures will be evaluated under Subsections 106.02 and 106.04.
Painting will be evaluated under Section 563.
Bearing devices will be evaluated under Section 564.
Measurement
555.20 Measure the Section 555 pay items listed in the bid schedule according to Subsection 109.02 and
the following as applicable:
Measure structural steel computed according to AASHTO, LRFD Bridge Construction Specifications.
Include metal items incidental to the structure and specified in the contract.
When measurement is by contract quantity, changes in quantities resulting from alternative details
proposed by the Contractor and accepted as a part of the drawings are not subject to adjustment according
to Subsection 109.05.
Payment
555.21 The accepted quantities will be paid at the contract price per unit of measurement for the Section
555 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
452
Section 556
Section 556. — BRIDGE RAILING
Description
556.01 This work consists of furnishing, erecting, removing, and resetting bridge railing.
Bridge railing is designated as concrete, steel, aluminum, or timber according to the predominant material
contained in the railing.
Material
556.02 Conform to the following Sections and Subsections:
Aluminum alloy for bridge rail
717.12
Aluminum bolt heads and nuts
717.13
Aluminum welding wire
717.14
Box beam rail
710.06(b)
Painting
563
Reinforcing steel
709.01
Steel structures
555
Structural concrete
552
Timber structures
557
Construction Requirements
556.03 General. Accurately place anchor bolts to provide correct and true alignment of the railing. Set
anchor bolts so that they project not more than ⅜ inch (10 millimeters) beyond the nut when tightened.
Chamfer or round by grinding or filing sharp exposed metal edges.
Do not erect railing until centering or falsework for the supporting span is removed. Construct bridge
railing so that it does not follow unevenness in the curb, sidewalk, or wall that supports the railing. Install
railing to present a smooth and uniform appearance in its final position. Set posts vertical.
556.04 Concrete Railing. See Section 552.
556.05 Steel Railing. See Section 555.
556.06 Aluminum Railing. See Section 555, except as amended by the following:
(a) Cutting. Material that is ½ inch (13 millimeters) thick or less may be cut by shearing, sawing, or
milling. Saw or mill material that is over ½ inch (13 millimeters) thick. Do not flame cut. Make cut
edges true, smooth, and without excessive burrs or ragged breaks. Fillet reentrant cuts by drilling
before cutting.
(b) Bending. Material may be heated to a maximum 400 °F (200 °C) for a period not to exceed
30 minutes to facilitate bending.
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Section 556
(c) Rivet and bolt holes. Drill rivet and bolt holes to finished size or subpunch smaller than the
nominal diameter of the fastener and ream to size. Subpunch to a diameter that is smaller than that of
the finished hole by at least one-quarter the thickness of the piece. Make the finished diameter of holes
not more than 7 percent greater than the nominal diameter of the fastener, except:
(1) Fabricate slotted bolt holes as required; and
(2) Fabricate anchor bolt holes up to 25 percent larger, not to exceed ½ inch (13 millimeters)
larger than the nominal bolt diameter.
(d) Welding. Weld according to AWS, Structural Welding Code - Aluminum, D1.2 (D1.2M).
(e) Contact with other material. Protect aluminum alloys that contact other material as follows:
(1) Aluminum alloys in contact with other metals. Coat the contacting surfaces with dielectric
aluminum-impregnated caulking compound or place a synthetic rubber gasket between the
surfaces.
(2) Aluminum alloys in contact with stone or concrete.
(a) Where a bond is not required. Coat the contacting surfaces with aluminum-impregnated
caulking compound or with heavy bituminous paint pigmented with aluminum powder or
paste.
(b) Where a bond is required. Coat the contacting aluminum surface with zinc-chromate paint.
Allow paint to dry before installation.
(3) Aluminum alloys in contact with wood. Coat the contacting wood surface with three coats of
paint according to Section
563 and coat the contacting aluminum surface with
aluminum-impregnated caulking compound.
556.07 Timber Railing. See Section 557.
556.08 Remove and Reset Bridge Railing. Remove and store the existing bridge railings and
appurtenances. Replace railings, supports, and hardware damaged during removal, storage, or resetting.
556.09 Painting. When required by the contract, paint according to Section 563.
556.10 Acceptance. Material (except concrete, painting, reinforcing steel, structural steel, and timber) for
bridge railings will be evaluated under Section 106.03. Submit a production certification with each
shipment of bridge railing.
Concrete will be evaluated under Section 552, except compressive strength will be evaluated under
Subsection 106.04.
Construction of bridge railings will be evaluated under Subsections 106.02 and 106.04.
Reinforcing steel will be evaluated under Section 554.
Structural steel will be evaluated under Section 555.
Timber will be evaluated under Section 557.
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Section 556
Painting will be evaluated under Section 563.
Measurement
556.11 Measure the Section 556 pay items listed in the bid schedule according to Subsection 109.02.
Payment
556.12 The accepted quantities will be paid at the contract price per unit of measurement for the Section
556 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
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Section 557
Section 557. — TIMBER STRUCTURES
Description
557.01 This work consists of fabricating, treating, erecting, and painting structural timber. This work also
includes required lumber and hardware.
Material
557.02 Conform to the following Section and Subsections:
Galvanized coatings (drains)
717.07
Hardware
716.02
Painting
563
Structural carbon steel (drains)
717.01(a)
Structural glued laminated timber
716.04
Treated structural timber and lumber
716.03
Untreated structural timber and lumber
716.01
Construction Requirements
557.03 General. Excavate and backfill according to Section 208.
Use slings or other devices to protect the corners of heavy timbers and banded packages of lighter timber.
Cut and form lumber and timber so joints have even bearing over their entire contact surface. Do not use
shims in making joints. Close all joints. Drive nail and spike heads flush with the wood surface.
Use the same end, face, and edge of the timber member for all layout dimensions. Bore holes from mating
faces.
557.04 Storing Material. Store material in an area cleared of weeds, rubbish, or other objectionable
material. Elevate material at least 8 inches (200 millimeters) above the ground. Provide sufficient support
to prevent sagging.
Open-stack untreated material to shed water. Allow for free air circulation by stacking material in layers
on stickers that extend across the full width of the stack. Align stickers vertically and space them at regular
intervals.
Close-stack treated material to shed water.
Protect material from the elements. Use water-resistant paper or opaque polyethylene film if material is be
covered. Do not use impervious membranes (such as polyethylene film) during dry weather. Slit or
puncture individual wrappings full length on the lower side to permit water drainage.
Store and protect glued laminated timber according to the AITC 111, Recommended Practice for
Protection of Structural Glued Laminated Timber During Transit, Storage, and Erection.
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Section 557
557.05 Holes for Drift Pins, Dowels, Bolts, and Lag Screws. Bore holes before preservative treatment.
Bore holes for round drift pins and dowels to a diameter 1/16 inch (1.6 millimeter) less than the diameter of
the pin or dowel. Bore holes for square drift pins and dowels to a diameter equal to the side dimension of
the pin or dowel.
Bore holes for galvanized bolts to a diameter 1/16 inch (1.6 millimeter) larger than the diameter of the bolt.
Bore holes for lag screws according to Subsection 7.3.1. of the AITC, Timber Construction Manual.
557.06 Treating Timber. Indicate the preservative used, penetration in inches (millimeters), retention in
pounds per cubic foot (kilograms per cubic meter) (assay method).
Cut, frame, and bore timbers before treatment when practical. Do not cut or bore timber below the
high-water mark in coastal waters.
Handle treated timber according to the AWPA published Consumer Information Sheet. Do not drip or spill
preservative into the aquatic environment or onto the ground. Handle treated timbers to prevent damage to
their surfaces. Do not use cant dogs, hooks, or pike poles.
Field treat cuts or abrasions with preservative. Dip, soak, spray, or apply three brush coats of the same
preservative according to AWPA M4, Standard for the Care of Preservative-Treated Wood Products.
Impregnate holes bored after treatment with the same preservative using tools suitable for proper
application. Plug unused holes with the same treated timber.
557.07 Hardware. Galvanize hardware and fasteners including nails, spikes, bolts, washers, and timber
connectors. Do not galvanize malleable iron or cast iron hardware.
Use washers under bolt heads and nuts in contact with wood. Use malleable iron washers with a diameter
approximately three times the bolt diameter. Use cast iron washers when the timber is in contact with the
ground. Use square washers only when specified.
Cut off excess bolt lengths of more than 1 inch (25 millimeters). After final tightening, check or burr bolts
with a pointing tool to prevent loosening of the nuts.
557.08 Countersinking. Countersink screws, bolts, and nuts where required. Treat countersunk recesses
with an approved preservative before filling, except in railings. Fill the recess with hot pitch or other
approved filler after bolts, screws, and nuts are in place.
557.09 Framing. Do not slab or trim treated piles when fitting sway or sash braces. Securely fasten braces
to smaller piles using treated blocks to fill the gaps.
557.10 Framing Bents. Firmly and evenly bed mud blocks to solid bearing. Tamp in place.
When concrete is cast, set dowels for anchoring sills and posts to project at least 6 inches (150 millimeters)
above the tops of the pedestals. Finish concrete pedestals supporting framed bents so that sills or posts bear
evenly on the pedestals.
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Section 557
Make sills bear evenly and true on mud blocks, piles, or pedestals. Bolt sills into place with drift bolts that
extend into the mud blocks or piles for at least 6 inches (150 millimeters). Where possible, remove
material in contact with sills for circulation of air around the sills.
557.11 Bent Caps. Make timber caps bear evenly and uniformly over the tops of aligned supporting posts
or piles. Secure caps with drift bolts extending at least 9 inches (230 millimeters) into the approximate
center of each post or pile.
557.12 Bracing. Bolt the ends of bracing through the pile, post, cap, or sill. Brace intermediate
intersections with posts or piles with bolts and spikes with wire, or boat spikes as required. Use galvanized
spikes in addition to bolts.
Make bracing bear firmly against the pile or cap to which it is bolted. Provide and place shims as
necessary to prevent bending of the bracing more than 1 inch (25 millimeters) out of true when bracing
bolts are tightened.
Where the space between the bracing and cap or pile is:
(a) Less than 1 inch (25 millimeters), shims are not needed;
(b) 1½±½ inches (38±13 millimeters), place two ogee washers with their narrow faces together or
other approved washers on each bolt that passes through the space; or
(c) Over 2 inches (50 millimeters), use wooden shims of the proper thickness.
Fabricate the wooden shims from the same treated wood used in the structure or white oak. Do not use
built-up wooden shims. Make wooden shims from a single piece of lumber with the width not less than
4 inches (100 millimeters) and the length not less than the width of the bracing measured along the cap or
pile. Do not adze, trim, or cut treated members to avoid the use of shims.
557.13 Stringers. Size stringers at bearings. Position stringers so knots near edges are in the top portion of
the stringer.
Outside stringers may have butt joints with ends cut on a taper. Lap interior stringers so both stringer ends
have full length bearing on a floor beam or cap. Stagger joints where stringers are two panels in length.
Separate lapped ends of untreated stringers by at least ½ inch (13 millimeters) for air circulation. Use drift
bolts to securely fasten the lapped ends.
Place cross-bridging at the center of each span. Cut cross-bridging members to provide full bearing on the
stinger sides at each end. Securely toenail the cross-bridging with at least two nails in each end. If blocking
is used, make it fit snugly and securely.
557.14 Plank Floors. Use plank that is surfaced on four sides (S4S).
Single-ply timber floors consist of a single thickness of planks supported on stringers. Grade plank
thickness so no two adjacent planks vary in thickness by more than ⅛ inch (3 millimeters). Lay the planks
heart side down with ¼ inch (6 millimeters) space between them for dry, seasoned material and with no
joint space for unseasoned material. Spike each plank securely to each stringer.
Two-ply timber floors consist of two layers of flooring supported on stringers. Treat the lower layer
according to Subsection 557.06. Lay the top layer either diagonally or parallel to the roadway centerline.
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Section 557
Stagger joints at least 36 inches (900 millimeters). Securely fasten each top layer member to the lower
layer. Where the top layer is placed parallel to the centerline of the roadway, use special care to securely
fasten the ends of the flooring. Bevel the ends of top layer members at each end of the structure.
557.15 Transversely Nail Laminated Decks. Use 2-inch (50-millimeter) nominal thickness laminations,
surface one edge hit or miss ⅛ inch (3 millimeters) scant (S1E-H or M ⅛-inch (3-millimeter) scant), and
one side hit or miss ⅛ inch (3 millimeters) scant (S1S-H or M ⅛-inch (3-millimeter) scant).
Place the laminations on edge and at right angles to the centerline of roadway. Attach each piece to the
preceding piece using galvanized spikes of sufficient length to pass through two pieces and at least
halfway through the third piece. Drive spikes at each end and at approximately 18-inch (450-millimeter)
intervals alternately diving near the top and bottom edges.
Where timber stringers are used, use spikes to toenail every other piece to every other stringer. When steel
stringers are used, securely attach the pieces using approved galvanized metal clips.
Use pieces of sufficient length to bear on at least four stringers. Do not splice pieces between stringers.
Space end joints on a stringer no closer than every third piece. Space end joints in adjoining pieces no
closer than every second stringer.
557.16 Glue Laminated Panel Decks. When handling and transporting, avoid bending panels, especially
transverse to the laminated pieces. When lifting a panel, support it at a sufficient number of points. Do not
drag or skid panels. Protect the panel edges from damage.
When dowels are used between panels, use a template or drilling jig to properly space dowel holes. Drill
holes the same diameter as the dowel and ¼ inch (6 millimeters) deeper than one half the dowel length.
Slightly taper or round dowel tips and lubricate dowels to facilitate the connection process.
Start the tips of the dowels partially and equally in the holes of the panels to be joined. Draw the panels
together, keeping the edges parallel, until the panels abut tightly. Securely fasten each panel to each
stringer.
557.17 Wheel Guards and Railings. Surface (S4S) wheel guards, rails, and posts. Place wheel guards in
not less than 12-foot (3.7-meter) lengths. Squarely butt-joint rails at posts.
557.18 Trusses. Avoid irregularities in alignment. In horizontal projection, fabricate chords straight and
true from end-to-end. In vertical projection, fabricate chords to a smooth, corded curve through panel
points conforming to the correct camber. Make bearing surfaces fit accurately. Do not make uneven or
rough cuts at the points of bearing.
557.19 Painting. When required by the contract, paint according to Section 563.
557.20 Acceptance. Material for timber structures will be evaluated under Subsections 106.02 and 106.03.
Submit a production certification with each shipment of structural timber and lumber. If treated, indicate
the preservative used, penetration inches (millimeters), retention in pounds per cubic foot (kilograms per
cubic meter) (assay method), and the "Best Management Practice" used in treating timber members.
Construction of timber structures will be evaluated under Subsections 106.02 and 106.04.
Painting will be evaluated under Section 563.
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Section 557
Measurement
557.21 Measure the Section 557 pay items listed in the bid schedule according to Subsection 109.02 and
the following as applicable:
When measuring untreated and treated structural timber and lumber by the thousand board feet measure
(cubic meters), measure in the structure.
Compute the quantities from nominal dimensions and actual lengths, except for transversely nail laminated
decks and glue laminated panel decks. Measure transversely nail laminated decks and glue laminated panel
decks in place after dressing.
Measure timber piles under Section 551.
Measure timber bridge rail under Section 556.
Payment
557.22 The accepted quantities will be paid at the contract price per unit of measurement for the Section
557 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
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Section 558
Section 558. — DAMPPROOFING
Description
558.01 This work consists of dampproofing concrete or masonry surfaces.
Material
558.02 Conform to the following Subsections:
Asphalt
702.03(b)
Primer
702.03(a)
Construction Requirements
558.03 Dampproofing. Cure the concrete or masonry surface according to Subsection 552.15, except do
not use liquid membrane curing compound. Allow concrete surface to dry at least 10 days after completion
of curing.
Apply dampproofing to a dry, clean, reasonably smooth surface that is free of dust and loose material.
Apply dampproofing in dry weather when the air and surface temperatures are 45 °F (7 °C) or higher.
Apply primer to the surface and allow it to dry. Apply two coats of asphalt at the rate of approximately
25 pounds per 100 square feet (1.25 kilograms per square meter) of surface per coat. Apply prime coat and
asphalt coats uniformly, fully covering the surface, and thoroughly work them into the surface. Make the
total of the final two asphalt coats approximately 332 inch (2.4 millimeters) thick. Allow asphalt coats to
harden before allowing contact with water or backfill material.
558.04 Acceptance. Material for dampproofing will be evaluated under Subsections 106.02 and 106.03.
Applying dampproofing will be evaluated under Subsections 106.02 and 106.04.
Measurement
558.05 Measure the Section 558 pay items listed in the bid schedule according to Subsection 109.02.
Payment
558.06 The accepted quantities will be paid at the contract price per unit of measurement for the Section
558 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this
Section. See Subsection 109.05.
461
Section 559
Section 559. — WATERPROOFING
Description
559.01 This work consists of waterproofing concrete surfaces. Waterproofing consists of in-place
membrane or preformed membrane systems.
Material
559.02 Conform to the following Subsections:
Asphalt
702.03(b)
Asphalt roll roofing
702.03(e)
Mastic
702.03(d)
Primer
702.03(a)
Sealants, fillers, and seals
712.01
Waterproofing fabric
702.03(c)
Construction Requirements
559.03 General. Store waterproof fabric in a dry and protected place. Do not store rolls standing on end.
Ensure the concrete surface is free of projections or depressions that might cause puncture of the
membrane. Clean the concrete surface of dust and loose material. Do not place membranes on wet
concrete. Do not place membrane on new concrete until at least 10 days after completion of the concrete
curing process as defined in Subsection
552.15. Apply waterproofing in dry weather when the
temperature is above 35 °F (2 °C) and rising.
Apply primer and membrane beginning at the lowest point of the work.
559.04 In-place Membrane System. Stir asphalt frequently as it is heated to a temperature between
300 and 350 °F (150 and 175 °C).
Apply hot asphalt at a rate not less than 12 gallons per 100 square feet (5 liters per square meter) on
finished horizontal surface and not less than 15 gallons per 100 square feet (6 liters per square meter) on
vertical surface.
Ensure placed fabric is mopped by end of shift.
Prevent water from getting between the waterproofing and the waterproofed surface at the edges and at
openings in the membrane for drains and pipes.
Provide flashing at curbs and against girders, spandrel walls, and other area with separate sheets that lap
the main membrane at least 12 inches (300 millimeters). Seal flashing with either a metal counter-flashing
or by embedding the upper edges of the flashing in a groove joint filler.
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Section 559
Provide horizontal and vertical expansion joints with sheet copper or lead in a "U" or "V" form. Fill the
joint with hot joint filler after the membrane has been placed. Carry the membrane continuously across
expansion joints. For joints that are essentially open joints, but are not designed to provide for expansion,
pack the joint with oakum and fill with hot-poured joint filler before placing the membrane.
At the ends of a structure, carry the membrane down the fill face of the abutment and provide for
movement.
Install material as follows:
(a) Apply a coat of primer and allow to dry;
(b) Mop a coat of hot asphalt slightly wider than half the width of waterproof fabric and cover the
entire area of concrete;
(c) Immediately roll a starter strip of half-width waterproof fabric into the asphalt. Press the waterproof
fabric into place to rid it of air bubbles and to conform it closely to the surface;
(d) Mop hot asphalt over the top of the starter strip to completely conceal the weave and an adjoining
section of concrete surface slightly wider than half the fabric width;
(e) Immediately roll a full-width strip of fabric into the fresh asphalt, pressing it into place as before;
(f) Mop this second strip and an adjoining section of concrete surface slightly wider than half the fabric
width;
(g) Place a third strip of fabric to lap the first strip by not less than 4 inches (100 millimeters). Continue
this process of lapping each strip of fabric at least 4 inches (100 millimeters) over the strip placed
before the last strip until the entire surface is covered with 2 layers of fabric. Lap the ends at least
12 inches (300 millimeters). Do not allow the fabric to touch an un-mopped surface; and
(h) Mop the entire surface with hot asphalt after all waterproof fabric has been placed.
Ensure laps are sealed.
Repair or replace waterproofing that leaks. Use patches extending at least 12 inches (300 millimeters)
beyond the outermost damaged portion, and extend the second ply at least 3 inches (75 millimeters)
beyond the first.
Apply protective covering according to Subsection 559.06.
559.05 Preformed Membrane System. Preformed membrane systems consist of a primer applied to the
prepared surface and a single layer of adhering preformed membrane sheet.
(a) Prime application. Install oil-resistant, adhesive-backed construction paper to mask expansion
dams or headers.
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Section 559
Thoroughly mix and apply primer by spray or squeegee to the entire area to be sealed. Apply the
neoprene-based primer in one coat at a rate of approximately 300 square feet per gallon (7 square
meters per liter). Apply resin or solvent-based primer in one coat at a rate of approximately 120 square
feet per gallon (3 square meters per liter). Continuously agitate the primer during application.
(b) Membrane installation. Place the membrane continuously over masked areas. Place the
membrane on neoprene-based primers within 36 hours, resin-based primers within 8 hours, and
solvent-based primers within 24 hours of placing the primer. If this time is exceeded, re-apply the
primer.
Place the membrane by hand or by mechanical methods. Lap membrane sheets in the direction of
water flow.
(1) Bridge decks.
(a) Install a 12-inch (300-millimeter) minimum width strip along the juncture of deck and base
of barrier railing or curb face at the low side of the deck with the sheet extending up the face
3 inches (75 millimeters);
(b) Starting at the gutter line, lay sheets longitudinally and side lapped with adjacent sheets by
not less than
2½ inches
(60 millimeters) and end lapped by not less than
6 inches
(150 millimeters);
(c) Place a 12-inch (300-millimeter) minimum width strip at the juncture of deck and base of
curb or railing at the high side of the deck extending up the face 3 inches (75 millimeters).
(d) At open joints, at deck bleeder pipes, and at other locations as needed, cut the membrane
sheet and turn into the joint or bleeder as the sheet is being laid; and
(e) For rubberized asphalt sheets and modified bitumen sheets, apply mastic as a bead along the
exposed edge of the membrane sheet that extends up the barrier railing or curb face and that
ends in the high-side gutter.
(2) Surfaces other than bridge decks. Conform to Subsection 559.05(b)(1) and the following:
(a) Place membrane vertically with each successive sheet lapped to the preceding by at least
3 inches (75 millimeters);
(b) Lap horizontal splices by at least 6 inches (150 millimeters);
(c) Place a troweled bead of manufacturer’s recommended mastic or sealing tape along
exposed edges of the installed membrane;
(d) Flash projecting pipe, conduits, sleeves, or other facilities passing through the preformed
membrane waterproofing; and
(e) Use prefabricated or field-fabricated boots, fitted coverings, or other devices as necessary to
provide watertight construction.
Roll the surface with hand rollers or other apparatus as necessary to develop a firm and uniform bond
with the primer and minimizes wrinkles and air bubbles.
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