Item 513 STRUCTURAL STEEL MEMBERS
513.01 Description
513.02 Fabricator
Approval Procedure
513.03 Levels of
Fabricator Qualification
513.04 General
513.05 Fabricator
Documentation Responsibility
513.06 Shop Drawings
513.07 Levels 1 through
6, Prefabrication Meeting
513.08 Materials
513.09 Material
Control
513.10 Care of
Material
513.11 Workmanship and
Straightening
513.12 Finish
513.13 Stiffeners
513.14 Fillers
513.15 Horizontally
Curved Beams and Girders
513.16 Joints and
Splices
513.17 Pin Holes
513.18 Pins and
Rollers
513.19 Holes for
High-Strength and Bearing Bolts
513.20 High-Strength
Steel Bolts, Nuts, and Washers
513.21 Welding
513.22 Stud Shear
Connectors
513.23 Threads for
Bolts and Pins
513.24 Shop Assembly
513.25 Nondestructive
Testing
513.26 Shipping,
Storage, and Erection
513.27 Shop Coating
513.28 Cleaning ASTM A
709/A 709M, Grade 50W (345W) Steel
513.29 Method of
Measurement
513.30 Basis of
Payment
513.01 Description. This work consists
of preparing shop drawings, furnishing and fabricating structural steel
members, nondestructive testing, fabricator performed quality control, documentation,
cleaning, shop coating, and erecting structural steel and other structural
metals. Prepare shop drawings and erect structural steel according to Item 501
and the additional requirements below. Shop painting shall conform to Item 514.
The work also includes any work to move existing steel structures to the plan
location, making necessary repairs and alterations, and connecting or joining
new and old construction.
The
terms “main,” “secondary,” or “detail,” as referred to in Item 513,
are defined as follows: “main” refers to material, members, and fasteners that
are primarily stressed by live load and structure weight; “secondary” refers to
material, members, and fasteners that do not directly support live load or main
members; “detail” refers to essential non-structural material, members, and
fasteners.
513.02 Fabricator Approval Procedure. Select
fabricators that are listed by the Department before the Contract letting date
as evaluated by the Office
of Materials Management and prequalified according to Supplement
1078.
The
Office
of Materials Management may accept subletting of processes that require
specialized machinery or knowledge. Submit written requests for
subletting to the Office
of Materials Management. The Office
of Materials Management will determine if the process is uncommon and will
evaluate the qualifications of the proposed sublet fabricator. The
fabricator’s quality control staff shall witness and perform quality control of
the sublet work.
513.03 Levels of Fabricator Qualification. There are
eight levels of fabricator qualification. The Office
of Materials Management will classify each fabricator at the highest level
of fabrication it is qualified to perform.
Level |
Description of Capabilities |
SF |
Standard fabricated members described and paid for as Item 516,
517,
and 518
and detailed by standard bridge drawings. Material and fabrication acceptance
by certification with random Department audits of the work and documentation. |
UF |
Unique fabricated members not covered by standard bridge
drawings and not designed to carry tension live load. Examples include
curb plates, bearings, expansion joints, railings, catwalk, inspection
access, special drainage, or other products. Examples also include
retrofit cross frames, retrofit gusset plates, retrofit lateral bracing, or
other miscellaneous structural members not included in Levels 1 through
6. Quality assurance of shop drawings, material test reports, and
inspection according to Item 513,
UF Level. |
1 |
Single span, straight, rolled beam bridges without stiffeners,
Secondary and Detail materials designed to carry tension live loads such as
retrofit moment plates. Case II Loading. Quality assurance of
shop drawings, material test reports, and inspection according to Item 513,
Levels 1 through 5. |
2 |
Multiple span, straight, rolled
beam bridges without stiffeners. Case II loading. Quality
assurance of shop drawings, material test reports, and inspection according
to Item 513,
Levels 1 through 5. |
3 |
Single or multiple span, straight,
dog legged, or curved, rolled beam bridges including stiffeners. Case I
or II Loading. Quality assurance of shop drawings, material test
reports, and inspection according to Item 513,
Levels 1 through 5. |
4 |
Straight or bent welded plate girder bridges. Case I
or II loading. Quality assurance of shop drawings, material test
reports, and inspection according to Item 513,
Levels 1 through 5. |
5 |
Straight, curved, haunched, or
tapered welded plate girder bridges. Case I or II loading.
Quality assurance of shop drawings, material test reports, and inspection
according to Item 513,
Levels 1 through 5. |
6 |
Truss bridges, fracture critical bridges, fracture critical
members, or fracture critical components new or retrofitted. Case I or
II loading. Quality assurance of shop drawings, material test reports,
and inspection according to Item 513,
Level 6. |
513.04 General. Perform all steel fabrication
including the shop application of coatings in a prequalified structural steel
fabricating shop consisting of adequately sized permanent buildings with
equipment, heat and light, and experienced personnel to satisfactorily perform
all necessary operations. Perform flame cutting, air carbon-arc gouging,
cambering, welding, cleaning, and painting inside permanent buildings that are
maintained at the required environmental conditions. The fabricator may
perform shop assembly of large pieces for fit-up of field connections
outdoors. These provisions will not apply to steel requiring fabrication
at the bridge site in the repair, alteration or extension of an existing
structure.
If
repairing, extending, or altering existing structures, take
measurements of the existing structure as required to accurately join old and
new work. Include these measurements on shop drawings. Measurements
shown on the plans that indicate the extent and nature of repair, alterations
or extension shall not relieve the Contractor of this responsibility.
At
least two weeks before starting shop fabrication, the fabricator shall notify
the Office
of Materials Management and furnish a proposed fabrication schedule for the
work.
Unless
the Office
of Materials Management provides a written waiver of a hold or witness
point inspection, the fabricator shall store members completed during the
inspector’s absence in a manner that allows the inspector to completely and
safely inspect the finished work.
The
fabricator shall not ship fabricated members performed under Item 513,
UF Level or Levels 1 through 6 from the shop without
prior hold point inspections unless the Office
of Materials Management waives the inspection. The Office
of Materials Management will not conduct the scheduled final inspection
until the fabricator completes and inspects with documentation, final
fabrication and shop coatings and the Contractor documents approval of shop
drawings and material test reports.
The
Office
of Materials Management will not conduct a final fabrication inspection of
SF Level members. Instead, the Office
of Materials Management will conduct random inspections during the
fabricator’s work.
The
fabricator shall provide an office with the following attributes:
A.
A minimum floor area of 120 square feet (11 m²).
B.
A minimum ceiling height of 7 feet (2.1 m).
C.
Adequate working and storage facilities with one locking file cabinet for the
exclusive use of the Department’s inspector, lighting, and electrical outlets.
D.
Provisions for heating to a minimum temperature of 68 °F (20 °C) and adequately
ventilated.
E.
A telephone with direct access to an outside trunk line for the exclusive use
of the inspector.
If
using steel stamps for identification purposes, use the “mini-stress” or “stressless” type.
513.05 Fabricator Documentation Responsibility. The
fabricator shall keep and maintain documentation records as specified in Supplement
1078.
At
the Department’s request, provide access to the above documents for audit, inspection,
and copying.
513.06 Shop Drawing. Provide shop drawings
conforming to 501.04
and the following requirements:
Include
details, dimensions, size of materials, match mark diagrams for field
connections, a diagram identifying, by some unique mark, each area of a welded
splice to be covered by a single radiograph, and other information necessary
for the complete fabrication and erection of the metal work.
For
multiple span beam and girder bridges, include an overall layout with
dimensions showing the relative unloaded vertical and horizontal position of
beam or girder segments with respect to a full length base or work line.
Account for camber and horizontal curvature of the beams or girders, and the
effect of deck surface profile in this layout. Show required offsets for
vertical and horizontal curvature at approximately each one-fourth of span
length, at field splices, and at bearing points. For horizontally curved
members, show the offset to a baseline strung from end to end of the member,
every 10 feet (3 m) of length.
Identify
the grade (ASTM designation), CVN, fracture critical,
or any special testing requirements for each piece of steel. Identify
pieces made of different grades of steel with different assembling or erecting
marks, even if the pieces have identical dimensions and detail.
Identify
the welding procedure by the WPS number at each joint
and the location and identification numbers of all radiograph tests.
Detail
structural steel to fit under full steel dead load and prior to deck placement
with the webs of primary members plumb.
513.07 Levels 1 through 6, Prefabrication Meeting. After
providing the notice and schedule required by 513.04
and at least 3 days after the Department receives shop drawings, conduct a
prefabrication meeting at the fabricator’s facilities, or another location
agreed to by all parties. The fabricator and its quality control specialists
for fabrication and painting, the inspector, and the Contractor, or its
designated representative, shall attend the meeting. The purpose of this
meeting is to review any fabrication issues, including information on shop
drawings, inspection, hold or witness points, unique fabrication items, special
processes, and both the fabrication and project schedule. The fabrication
quality control specialist shall conduct the meeting and record and distribute
meeting minutes that document all issues discussed. Fabrication may begin
after the prefabrication meeting is complete.
513.08 Materials. Furnish materials conforming to 501.06.
513.09 Material Control. Identify
and mark each piece of steel according to the shop drawings and the following
requirements.
Immediately
after removing steel that is furnished in tagged lifts or bundles, mark the
individual pieces of steel with the ASTM A 6/A
6M specification identification color code and heat number.
The
fabricator may furnish material from stock that is marked with the heat number
and mill test report.
If
separated from the full-size piece furnished by the supplier, mark excess
material placed in stock for later use with the heat number and, if provided,
with the ASTM A
6/A 6M specification identification color code.
During
fabrication, clearly and legibly mark the specification identification color
code and heat number on each piece of steel.
Before
cutting steel into smaller size pieces, clearly and legibly mark each smaller
size piece with the ASTM A 6/A 6M specification identification color code and
heat number.
Unless
otherwise approved by the inspector, mark pieces of steel that will be subject
to fabricating operations such as blast cleaning, galvanizing, heating for
forming, or other operations that may obliterate paint color code and heat
number markings with steel stamps or with a substantial tag firmly attached to
the piece of steel. At locations acceptable to the Office of Materials
Management, stamp the heat numbers into main material tested for CVN.
Issue
cutting instructions by cross-referencing the assembly marks shown on the shop
drawings with the corresponding item covered on the mill purchase order.
The fabricator’s system of assembly-marking individual pieces of steel and
issuing cutting instructions shall provide a direct reference to the appropriate
mill test report.
The
fabrication quality control specialist shall provide the Engineer with a letter
documenting that the fabricator performed material control according to this
specification.
513.10 Care of Material. Store structural material at the shop or field above the ground,
upon platforms, skids, or other supports. Use straight structural
steel with clean and dry surfaces before working it in the shop. Before
using, clean all rusted or corroded material. Only use this material if
it conforms to ASTM A 6/A 6M thickness tolerances after cleaning.
513.11 Workmanship and Straightening. If
necessary to straighten rolled material, use methods that will not damage the
member. If carefully planned and supervised, apply localized heat for
straightening. Do not allow the temperature of the heated area to exceed
1150 °F (620 °C) as controlled by pyrometric stick or
thermometers. Do not quench to accelerate cooling. Do not kink or
offset the material if using mechanic or hydraulic force to camber or
strengthen material. Do not cold bend fracture critical materials.
Camber rolled
beams as shown on the plans in the prequalified fabricating shop using heat or
hydraulic jacks. Control heating as specified above and follow a formal
shop heating procedure. Camber plate girders by
trimming web plates before assembly. During fabrication, shipping,
and erection, support and handle members to maintain camber.
Fabricate
structural steel to within the dimensional tolerances specified by Articles 3.5
of the AASHTO/AWS Bridge Welding Code, with the following
modifications:
A. Waviness, the
deviation of the top or bottom surface of a flange from a straight line or plan
curvature, shall not exceed 1/8 inch (3 mm) when the number of waves in a
10-foot (3 m) length is four or less, or 1/16 inch (1.6 mm) when more than
four, but sharp kinks or bends shall be cause for rejection.
B. For the measurement
of camber during lay down, position the bearing points both horizontally and
vertically to plan dimensions ±1/8 inch (±3 mm).
C. Measure camber as the
vertical offset between the steel and the common base line extending from
abutment bearing to abutment bearing. The maximum camber tolerance at
mid-span shall be 0 inch (0 mm) and the greater of +3/4 inch (+19 mm) or the
designed haunch height. Prorate the maximum camber tolerance at mid-span
between the center of the span and each adjacent bearing to provide a smooth
unbroken curve.
D. Permissible
difference in horizontal curvature of top and bottom flange at any point on
centerline of member, when measured as specified in 3.5.1.4, shall not exceed
3/8 inch (10 mm)
513.12 Finish. Plane sheared edges of all main
material to a minimum depth of 1/4 inch (6 mm) except for ASTM A
709/A 709M, Grade 36 (250) steel having a thickness of 5/8 inch (16 mm) or
less. Remove fins, tears, slivers, and burred or sharp edges from steel
members by grinding. If these conditions appear during the blasting
operation, re-grind and re-blast the steel members to the required surface
profile.
The fabricator may flame cut structural steel. Provide a smooth surface, free from cracks and notches, and use a mechanical guide to provide an accurate profile. Roll and flame cut surfaces according to the AASHTO/AWS Bridge Welding Code , as amended by Supplement 1011.
Provide
a surface finish for bearing and base plates and other bearing surfaces that
contact each other or concrete according to ANSI B46.1, Surface
Roughness, Waviness and Lay, Part I.
ANSI B46.1
Steel slabs |
2000 mil |
(50.0 µm) |
Heavy plates in contact in shoes to be welded |
1000 mil |
(25.0 µm) |
Milled ends of compression members, milled or ground ends
of stiffeners and fillers |
500 mil |
(12.5 µm) |
Bridge rollers and rockers |
250 mil |
(6.4 µm) |
Pins and pin holes |
125 mil |
(3.2 µm) |
Sliding bearings |
125 mil |
(3.2 µm) |
513.13 Stiffeners.
Place the bearing end of bearing stiffeners flush and square with the web and
in a manner so at least 75 percent of the area of the bearing end is in contact
with the inner surface of the flange. The other end of the bearing
stiffener shall have a tight fit as defined below. Position
bearing stiffeners to be vertical after erection. Weld
intermediate stiffeners that are not used in pairs to the compression flange,
and provide a tight fit for the tension flange. Weld intermediate
stiffeners connected to cross frame angles to the top and bottom flange.
A
tight fit is defined as the contact between the stiffener and flange over some
portion of the end of the stiffener and having no gap greater than 1/16 inch
(1.6 mm).
Clip
stiffeners 2 1/2 inches (65 mm) along the web and 1 inch (25 mm) along the
flange to clear flange-web welds and fillet or rolled shapes.
When
attaching stiffeners to the web and flanges, do not extend welds to the edge of
the stiffeners or into the clip area. Terminate these welds 1/4 ±1/8 inch
at the flange connections and 1/2 ±1/4 inch at the web connection.
513.14 Fillers.
Detail the shop drawings to show fill plates that compensate for the
misalignment of abutting elements due to differences in thickness of flanges
and webs at the splice locations. Detail the fill plates to the nearest
1/16 inch (1.6 mm) in thickness, but not less than 1/8 inch (3 mm) thick.
However, in the final shop assembly, furnish fills of sufficient thickness to
compensate for misalignment of abutting elements due to standard rolling mill
tolerances or due to differences in thicknesses of flanges and webs at the
splice location. The actual fills used shall compensate for differences
in total thickness or relative positions of more than 1/16 inch (1.6 mm) but
with no fills less than 1/8 inch (3 mm) thick. Provide fill plates in
bolted joints that are flush with the perimeter of the splice plates.
513.15 Horizontally Curved Beams and Girders. If members are to be heat curved, submit the
detailed procedure, including necessary calculations, to the Office
of Materials Management. Obtain the Office
of Materials Management’s acceptance of the procedure before starting this
work.
Curve
beams and girders using heat according to AASHTO
Standard Specifications for Highway Bridges, except that the fabricator
may cut flanges for girders to obtain the required alignment.
513.16 Joints and Splices. In bolted construction where tension or flexural
members are spliced, maintain a clearance of not more than 1/4 inch (6 mm)
between the abutting surfaces of spliced members. For spliced compression
members, face the abutting surfaces to provide a uniform bearing when properly
aligned and completely bolted.
In
welded construction, prepare abutting surfaces as shown on the shop
drawings. Verify the preparation for field welded butt joints in main
members by a complete shop assembly according to 513.24.
513.17 Pin Holes.
Bore pin holes after the member is fabricated and true to size, at right angles
to the axis of the member and parallel to each other. Pin holes for up to
5-inch (127 mm) diameter pins shall not exceed the pin diameter by more than
0.020 inch (0.51 mm) and pin holes for larger pins shall not exceed the pin
diameter by more than 0.031 inch (0.79 mm).
513.18 Pins and Rollers. Use pins and rollers made from cold rolled steel,
accurately turned to size, straight and smooth, and entirely free from
flaws. Pins over 9 inches (230 mm) in diameter shall be annealed.
In pins larger than 9 inches (230 mm) in diameter, bore a hole
not less than 2 inches (50 mm) in diameter the full length of the axis.
Furnish one pilot and one driving nut for each size of pin.
513.19 Holes
for High-Strength Bolts and Bearing Bolts. Provide cylindrical holes, perpendicular to the
member, clean cut, and free of ragged edges. Remove burrs by
countersinking not more than 1/16 inch (1.6 mm) or by grinding. Provide
finished holes with a diameter not larger than the nominal diameter of the bolt
plus 1/16 inch (1.6 mm). The hole diameter shall
not vary by more than 1/32 inch (0.8 mm) from a true circle for 85 percent of
the holes in a contiguous group, and not more than 1/16 inch (1.6 mm) for
the remainder.
Punch
holes using a die with a diameter not exceeding that of the punch by more than
1/16 inch (1.6 mm). Ream and drill holes using twist drills and twist
reamers. Wherever possible, direct the reamer by mechanical means.
Sub-drill
holes 3/16 inch (5 mm) less in diameter than the nominal diameter of the bolt,
and ream the holes to size with the parts assembled, except:
A. The fabricator may sub-punch main
material conforming to ASTM A
709/A 709M, Grade 36 (250) steel that is less than 3/4 inch (19 mm) thick,
and Grade 50 (345) or 50W (345W) steel that is less than 5/8 inch (16 mm)
thick.
B. The fabricator may drill full-size
holes in materials assembled and adequately clamped together.
C. The fabricator may punch full-size
holes in secondary and detail material conforming to ASTM A 709/A 709M, Grade 36
(250) steel that is less than 3/4 inch (19 mm) thick, and Grade 50 (345) or 50W
(345W) steel that is less than 5/8 inch (16 mm) thick.
D. The fabricator may make assemblies
such as floor beams connected to girders and rolled beam spans connected by
diaphragms through steel templates.
Place
all sub-punched or sub-drilled holes with sufficient accuracy such that after
assembling (before reaming) a cylindrical pin 1/8 inch (3 mm) smaller than the
nominal size of the punched hole may be entered perpendicular to the face of
the member without drifting in not less than 75 percent of the contiguous holes
in the same plane. All holes shall allow a pin 3/16 inch (5 mm)
smaller than the nominal size of the punched holes to be inserted in the above
manner.
Do
not plug located holes without written approval from the Office of Materials
Management.
Provide
steel templates with hardened bushings in holes that are accurately located in
relation to the centerline of the connection as inscribed on the
template. The fabricator is not required to use hardened bushings when
using a roto-broach, shell drill, or other similar
tool, to make the holes.
Ream
and drill holes through multiple piles only if the plies of the joint are held
tightly together with bolts or clamps and if sub-punched or sub-drilled, only
if the joint is pinned. Disassemble and clean the piles of burrs and
shavings before final assembly.
The
Contractor may drill or punch bolt holes full sized in unassembled pieces or
connections, including templates for use with matching sub-sized and reamed
holes, using suitable numerically controlled (N/C) drilling or punching
equipment. If using N/C drilling or punching equipment,
demonstrate the accuracy of the drilling or punching procedure to the inspector
according to 513.24.
After
holes are reamed or drilled full size, 85 percent of the holes in any
contiguous groups shall have no offset greater than 1/32 inch (0.8 mm) between
adjacent plies. The remainder of the holes shall not be offset more than
1/16 inch (1.6 mm) between adjacent plies.
If
requested in writing, the Office
of Materials Management may consider other methods of preparing holes for
high-strength bolts.
513.20 High-Strength
Steel Bolts, Nuts, and Washers.
Provide high-strength steel bolts, nuts, and washers conforming for all bolted
connections including erection bolts for cross frames and lateral bracing to 711.09.
A. General. Provide the Engineer with access to the work
for observing the installation and the tightening and checking of the bolts.
Determine the
required bolt length by adding the value from Table
513.20-1 to the grip. The table values include an allowance for
manufacturing tolerances and provide a bolt length for threads to protrude
through the nut. Add 5/32 inch (4 mm) for each hardened flat washer used
and 5/16 inch (8 mm) for each beveled washer used. Adjust the length, as
determined by Table 513.20-1, to the next longer 1/4 inch (6 mm); when
installed, the end of the bolt shall be flush with or project several thread
lengths outside the face of the nut.
Bolt Size (inches) |
To determine required bolt length,
add to grip[1] (inches) |
1/2 |
11/16 |
5/8 |
7/8 |
3/4 |
1 |
7/8 |
1 1/8 |
1 |
1 1/4 |
1 1/8 |
1 1/2 |
1 1/4 |
1 5/8 |
1 3/8 |
1 3/4 |
1 1/2 |
1 7/8 |
[1]
Total thickness of all connected material excluding washers.
TABLE 513.20-1M
Bolt Size (mm) |
To determine required bolt length,
add to grip[1] (mm) |
M16 |
24 |
M20 |
28 |
M22 |
31 |
M24 |
35 |
M27 |
38 |
M30 |
41 |
M36 |
47 |
[1]
Total thickness of all connected material excluding washers.
Use bolts, nuts, and
washers with a residual coating of lubricant when received. Bolts, nuts,
and washers without their original lubrication shall not be used.
B. Preparation. With the exception of metalizing, galvanizing,
and both organic zinc and inorganic zinc primers, remove coatings from joint
surfaces, including surfaces adjacent to the bolt heads, nuts, and
washers. Remove lacquer, dirt, oil, loose scale, rust, burrs, pits, and
other substances or defects that prevent solid seating of the parts or interfere
with the development of complete frictional contact. Do not place gaskets
or other yielding material between joint surfaces.
C. Installation. For each bolt, place a hardened washer under
the element (nut or bolt head) turned in tightening. If an outer face of
the bolted parts has a slope of more than 1:20 with respect to a plane normal
to the bolt axis, use a smooth beveled washer to compensate for the lack of
parallelism.
If necessary, the
Contractor may clip washers, at one location, not closer than seven-eighths of
the bolt diameter from the center of the washer.
During final assembly
of the parts to be bolted, first install a sufficient number of drift pins to
provide and maintain accurate alignment of holes and parts, then a sufficient
number of bolts tightened to a snug tight condition to bring all the parts of
the joint into complete contact. Replace any bolts that were installed
before installing drift pins. Before releasing the member from the
hoisting equipment, fill half the holes with drift pins and bolts tightened to
a snug tight condition in at least 50 percent of the
holes (preferably, half pins and half bolts) but use at least two drift pines
in each flange and web of each beam or girder. Install bolts starting at
the most rigidly fixed or stiffest point and progress toward the free edges.
Use cylindrical drift
pines that are not more than 1/32 inch (0.8 mm) smaller than the hole diameter.
Bolts are snug tight
when an impact wrench begins to impact the nut or when a man applies full
effort using an ordinary spud wrench.
Install bolts in the
remaining open holes and tighten the bolts to a snug tight fit, after which all
bolts shall be tightened completely by the turn-of-nut method.
Where difficulty is
experienced with the fit of the connection and the bolts are used to draw the
elements into contact, check all bolts in the affected portion of the
connection for a sustained snug tight condition.
Replace drift pins
with completely tightened bolts only after all the remaining holes are filled
with completely tightened bolts.
Do not field ream
holes drilled full size during fabrication.
After bolts are snug
tight, the wrench operator shall match-mark the outer face of the nut with the
flush or protruding portion of the bolt using a crayon or paint. The
Engineer will use the match-marks to determine the relative rotation between the
bolt and nut during final tightening using the turn-of-the-nut method.
Commence tightening
at the most rigidly fixed or stiffest point and progress toward the free edges,
both in the initial snugging up and in the final tightening. If required
because of wrench operation clearances, tightening may be done by turning the
bolt. If used, provide impact wrenches of adequate capacity to perform
the required tightening each bolt in approximately 10 seconds.
Do not reuse
galvanized A 325 bolts. Re-tightening previously tightened bolts that
became loose by tightening adjacent bolts is not reuse.
Follow the additional
bolting requirements in 513.26.
D. Bolt Tension. When all bolts in the joint are tight, the
minimum bolt tension for each bolt size is shown in Table 513.20-2.
Bolt Size (inches) |
Bolt Tension[1] (kips), minimum A 325 |
1/2 |
12 |
5/8 |
19 |
3/4 |
28 |
7/8 |
39 |
1 |
51 |
1 1/8 |
56 |
1 1/4 |
71 |
1 3/8 |
85 |
1 1/2 |
103 |
[1]
Equal to 70 percent of specified minimum tensile strengths of bolts,
rounded off to the nearest kip.
TABLE 513.20-2M
Bolt Size (mm) |
Bolt Tension[1] (kN),
minimum A 325M |
M16 |
91 |
M20 |
142 |
M22 |
176 |
M24 |
206 |
M27 |
267 |
M30 |
327 |
M36 |
475 |
[1]
Equal to 70 percent of specified minimum tensile strengths of bolts,
rounded off to the nearest kN.
TABLE
513.20-3 NUT ROTATION FROM SNUG TIGHT CONDITION
Bolt Length |
Disposition of Outer Faces of
Bolted Parts |
||
Both faces normal to bolt axis |
One face normal to bolt axis and other face sloped not more
than 1:20 (bevel washer not used) |
Both faces sloped not more than 1:20 from normal to bolt
axis (bevel washer not used) |
|
Up to and including 4 diameters |
1/3 turn |
1/2 turn |
2/3 turn |
Over 4 diameters but not exceeding 8 diameters |
1/2 turn |
2/3 turn |
5/6 turn |
Over 8 diameters but not exceeding 12 diameters |
2/3 turn |
5/6 turn |
1 turn |
Attain the bolt
tension specified in Table 513.20-2 by tightening all
bolts, the applicable amount of nut rotation specified in Table 513.20-3 by the
turn-of-nut method.
Nut rotation is
relative to bolt, regardless of the element (nut or bolt) being turned.
Tighten bolts requiring 1/2 turn and less within ±30 degrees and tighten bolts
requiring 2/3 turn and more within ±45 degrees.
1.
The Engineer will inspect the first completed connection of each bridge
according to 513.20.E.2 below and subsequent
connections the Engineer deems necessary. Thereafter, where the Engineer
has approved the joint compactness and snug-tight condition of bolts prior to
bolt tightening by the turn-of-nut method, the bolt tension as required in Table 513.20-2 shall be considered as attained if the
amount of nut rotation specified by Table 513.20-3 is
verified by the required match-marking.
2.
Furnish and use manual torque wrenches to inspect bolts. Perform test to
the satisfaction of the Engineer. Calibrate the inspection torque
wrenches at least once each workday using a device, approved by the Engineer,
and capable of indicating bolt tension. Use three bolts, placed and
tensioned individually, representative of the grade, size, length, and
condition used in the structure to determine the job inspection torque
according to 513.20.E.3. Place a washer under
the part being turned.
3.
Tighten each of the three representative bolts, using any convenient manner, to
the tension shown in Table 513.20-2. Then,
using the inspection wrench, apply a slow steady pull to the tightened bolt and
measure the torque required to turn the nut or head 5 degrees, approximately 1
inch (25 mm) at a 12-inch (300 mm) radius in the tightening direction.
Use the average torque measured in the tensioning of the three bolts as the job
inspection torque.
4.
With the Engineer present, randomly select for inspection two bolts or 10
percent of the bolts, whichever is greater, from each connection represented by
the 3-bolt sample described in 513.20.E.2.
Using the inspection wrench, apply the job inspection torque in the tightening
direction. The Engineer will accept the connection if the job inspection
torque does not turn the nut or bolt head. If the job
inspection torque turns a nut or bolt head, apply the job inspection torque to
all the bolts in the connection and reinspect the
connection as described above.
F. Calibration Devices. The manufacturer of the calibration device or a
qualified testing laboratory shall periodically examine each calibration device
at least once each year and other times if requested by the Engineer.
After calibration, the manufacturer or testing laboratory shall certify that
each calibration device accurately indicates the actual bolt tension.
513.21 Welding.
Perform welding by the shielded metal-arc, submerged arc, flux cored arc, or
stud welding process. Only shielded metal arc (stick) welding is
prequalified. All other welding processes require testing and approval by
the Office of Materials Management. Consideration will be given to other
methods of metal-arc welding if a written request is submitted to the Office of
Materials Management.
In other
respects, the AASHTO/AWS Bridge Welding Code,
as amended by Supplement
1011, shall govern the work.
Post copies of
the shop welding procedures at each welding location.
Weld only fracture critical and main members when the fabrication
quality control specialist and inspectors are physically at the facility.
The fabricator shall not perform fracture critical welding without prior
scheduling with the fabrication quality control specialist and the
inspector. The fabrication quality control specialist shall witness the
minimum percentages specified in Supplement
1078 and shall check all welding processes.
For non-fracture
critical welds, the fabrication quality control specialist shall perform
frequent inspections, and check all welding processes.
513.22 Stud Shear Connectors. Perform stud welding according to the AASHTO/AWS Bridge Welding Code, as amended by Supplement
1011, and this subsection.
In addition to
the stud bend tests of Article 7.6.6.1 of the AASHTO/AWS Bridge Welding Code, perform bend tests of
stud shear connectors at the start of each workday, when welding has been
interrupted for an hour or more, when changing grounds, when changing weld
settings, and when changing cable loop due to arc blow. Do not weld more
than 500 studs without the welds being field bend tested in accordance with the
specified procedure. The Contractor may leave in the bent position tested
studs that show no sign of failure, as determined by the Engineer.
Weld stud shear
connectors to the top flanges of beams or girders after the steel has been
erected and suitable scaffolding or deck forming has been provided. Studs may
be welded to beam or girder webs, end dams, bearing plates, or to other
secondary members and detail material in the shop. For galvanized structures
with welded shear connectors, remove the galvanic coating by grinding at each
connector prior to painting.
513.23 Threads for Bolts and Pins. Threads for pins shall conform to the Unified
Standard Series ANSI B1.1-UNC
(ANSI B1.13M) Class 2A (6g) for external threads and Class 2B (6H) for internal
threads, except that pin ends having a diameter of 1 3/8 inches (35 mm) or
more shall be threaded 6 threads to the inch (4.23 mm/thread).
513.24 Shop Assembly. Remove paint, grease, oil, rust, loose mill scale,
and protruding edges or burrs from all contact surfaces. Unless waived by
the Office of Materials Management, do not assemble and weld flanges and webs
to form girders or other similar members and do not accomplish fabrication or
assembly that interferes with the repair of a butt weld until the fabrication
quality control specialist for the A rated fabricators or the inspector for B
and C rated fabricators examines and approves radiographs of all butt welds in
the component parts.
Perform fit-up
work with the members assembled in unloaded positions as shown on the shop
drawing layout required by 513.06. During shop
assembly, adequately support members, especially at joints, to prevent
misalignment or deflection and designate supports that prevent settlement
during the fit-up, reaming or drilling of connections. The fabrication
quality control specialist shall maintain records of the actual horizontal and
vertical dimensions and relative positions of each assembly for each offset
required by 513.06 and, upon request, furnish a copy to
the inspector. Reposition members that become a part of two assemblies
for the second assembly to the dimensions recorded for the first assembly.
Using steel
stamps, match-mark all connecting parts assembled in the shop for the purpose
of reaming or drilling of holes for field connections or for fit-up of field
welded connections before disassembly. Punch mark bearing centerlines.
Continuous
beam and plate girders, including sections adjacent to hinged, pin connected,
sliding, or rocker bearing joints, shall have at least three adjacent segments
assembled, and holes reamed or drilled while assembled. Check the fit-up
of field welded connections by similar shop assembly.
Shop
assemble longitudinal or transverse beams and girders that are either framed or
connected by diaphragms and floor beams to check fit-up of connections to be
field welded, or to ream or drill holes for bolted connections. Assemble
trusses in lengths of at least three abutting panels before drilling or reaming
field connections.
Include
deck plates in the final shop assembly of bridges that
involve railroad deck plates, even if welding of these deck plates takes
place in the field.
If
the fabricator elects to use numerically controlled drilling or punching, the
required assembly shall be performed as specified above. The Office of
Materials Management will consider the Contractor’s written request to use
other methods of checking hole alignment and match
marking. If the Office of Materials Management does not consider, or
disapproves the fabricator’s proposed methods of assembly, perform the work
according to 513.19 and 513.24.
After
fabrication, shop assemble deck expansion devices to
check fit-up, straightness, and roadway cross-slope changes. Full width
assembly is required with phased construction if expansion devices have
interlocking fingers or have mechanical devices that require exact field
alignment.
The
fabricator may fabricate part-width deck segments without the required shop
assembly under the following conditions:
A. The plans require a phased
construction sequence.
B. Shop drawings incorporate a lay down,
similar to 513.06, defining vertical offset dimensions
from a full length common baseline to all roadway changes including sidewalks,
rounding, crowns, and field splice points of the expansion device.
Secure
parts not completely assembled in the shop with temporary bolts to prevent
damage in handling and shipping. In the shop, bolt field splice plates
into final position shift the splice plates laterally with respect to their
final position so that the ends of the plates are flush with the ends of the
member. Without the Office of Materials Management’s written acceptance,
do not weld or tack-weld to bolted assemblies. Perform authorized welding
according to 513.21.
513.25 Nondestructive Testing. Nondestructive testing shall conform to the AASHTO/AWS Bridge Welding Code, as amended by Supplement
1011 and as specified below.
As
the Engineer directs, perform ultrasonic or radiographic inspection of field
welded repairs in main members for thick scabs, deep kerfs or nicks, and
similar gross flaws. Ensure that all examined welds and base metal
adjacent to a welded joint conform to the quality requirements specified in 513.21. Submit radiographs, field sketches showing
specific locations, lengths and depths of the repair, and two copies of the
radiographic or ultrasonic technical reports to the Office
of Materials Management for acceptance. Receive the Office of
Materials Management’s acceptance before performing construction activities
making welds inaccessible for repair.
The
Contractor or fabricator shall notify the Department at least 48 hours before
performing nondestructive testing. Provide this notice even if specific
hold or witness point inspections are not required by Supplement
1078.
The
Office of Materials Management has the final authority to accept welds and will
resolve controversies regarding the interpretation of radiographs, magnetic
particle indications, or the acceptability of welds.
A. Radiographic Inspection of Welds. Before inspection, grind welds smooth. Grind
web splices only where radiographed, except grind outside fascia surfaces the
full length. Inspect the following welds:
1.
The full length of all butt welds in flange material of plate girders or rolled
beams. One hundred percent of butt welds in back up bars that remain in
the structure.
2.
The top and bottom one-third of transverse web splices in plate girders or
rolled beams and show any cope holes. If an unacceptable weld occurs,
radiograph an adjoining 12-inch (300 mm) length of weld not previously
inspected. If unacceptable flaws are found in this adjoining segment,
radiograph the remainder of the weld.
3.
Butt welds in longitudinal stiffeners attached to tension areas of webs.
4.
Twenty-five percent of each longitudinal web splice as selected by the
inspector.
5.
Full length of field flange cut repairs.
6.
Other welds specified in the Contract or AASHTO/AWS Bridge Welding Code.
Use a steel stamp to
make the radiograph identification mark shown on the shop drawing layout in the
area marked “Weld Identification” of Figures 6.1A through 6.1D of the AASHTO/AWS Bridge Welding Code in a manner to make it
visible in the radiograph of the area without resorting to superimposed like
markings. Place steel stamped identification marks on flange plates so
that after girder assembly the marks are on the inside of flange and outside
the area fastened to the web. Identify films of repaired welds by the
letter “R”. Do not place steel stamped identification numbers within the
weld area. Use superimposed characters to make other required markings.
Use film locations or
a technique employed that will show the top and bottom images of the plate
edge. Use films 4 1/2 ´ 17 inches (114 ´ 432 mm) where practical and a
minimum film size of 4 1/2 ´ 10 inches (114 ´ 254 mm).
Supply a technical
report for the RT testing similar to Annex III Form
III-5 of the AASHTO/AWS Bridge Welding Code,
and include the following: Project identification, member piece mark,
description of the repairs made, and the qualification level of the technician.
The Department will
take ownership of contact films. For main material repairs, provide
sketches that clearly show specific locations, lengths and depths of field cuts,
or damages repaired by field welding.
B. Magnetic Particle Inspection of Welds. Before magnetic particle inspection (MPI), complete welding required to fabricate each beam or
girder, correct all visual defects, and clean the weld. If the
fabricator’s quality control plan is acceptable to the Department and
additional processing does not produce a potential for cracking, the Department
may allow the Contractor to perform MPI before
complete welding.
Inspect welds using
the procedure and techniques for the dry powder magnetic-particle examination
of welds using the prod or the yoke method according to AWS
6.7.6. The prod test equipment shall have a functioning ammeter.
Provide a prod magnetizing current of 100 amperes per inch (25 mm) of prod
spacing but not less than 400 amperes. Use only aluminum prods.
Inspect at least 1
foot (0.3 m) for every 10 feet (3 m), or fraction thereof, for each size of
weld in the following:
1.
Flange-to-web welds, including ends of girder after trimming.
2.
Moment plate to flange welds.
3.
Bearing stiffener welds.
4.
Other welds specified in the Contract or AASHTO/AWS Bridge Welding Code.
5.
Field weld repairs as directed by the Engineer.
The inspector or the
fabrication quality control specialist will select random test sections.
Unless waived by the Office of Materials Management, the inspector will observe
inspection by C-rated fabricators. Position test
sections as necessary for the inspection and after considering the safety and
convenience to the inspecting personnel.
If a test section
contains unacceptable defects, test 5-foot (1.5 m) segments on both sides of
the test section, or, if less than 5-foot (1.5 m) segments are on both sides of
the test section, test the full length of the weld. Retest welds
requiring repair after repairs are complete. If the fabricator’s quality
control plan is acceptable to the Department and additional processing does not
produce a potential for cracking, the (WHO) may allow the Contractor to perform MPI before complete welding.
MPI will not locate all surface defects of Article 9.21
of the AASHTO/AWS Bridge Welding Code. Unacceptable
welds have MPI results that indicate defects exceed
the above quality standards.
For each unacceptable
defect, the fabricator shall record the piece mark, the location of the defect
on the member, the defect description, and the proposed repairs.
C. Ultrasonic Testing of Welds. Perform ultrasonic inspection of the following
welds:
1.
Complete joint penetration flange-to-web, T, or corner joint welds: 25 percent
for non-FCM, 25 percent compression or shear FCM, and 100 percent tension FCM.
2.
Complete penetration butt welds: 100 percent tension FCM
and 25 percent compression FCM.
3.
Other welds: as specified in the Contract or AASHTO/AWS Bridge Welding Code.
The fabrication
quality control specialist shall provide the Engineer with specified
certification, sketches, technician reports, and a letter documenting that the
Contractor performed nondestructive testing according to this specification.
513.26 Shipping, Storage, and Erection. Repair or replace, at the discretion of the Office
of Materials Management, members damaged by improper handling, storing, or
erection.
During
transportation, place adequate blocking between members to prevent movement and
facilitate unloading. Unless reinforced by additional plates,
angles, or other material bolted in place, do not use field connection holes
for tie-down. Band together bearing components.
Place material
stored in the fabricating shop or in the field on skids or blocks to prevent
the metal from contacting the ground. Place and shore girders and beams
in an upright position for shipping, and field and shop storage. Field
splice plates shall be bolted with temporary bolts, which shall be removed and
replaced, when field splice plated are placed in their final position or
shifted laterally with respect to their final position. Keep material
clean and properly drained. Install bearing devices and anchorages
according to Item 516.
Thoroughly clean
bearing surfaces and surfaces to be in permanent contact before the members are
assembled in the field.
Before erecting
structural steel, completely bolt up field splices and connections that started
before steel erection.
During erection,
the Engineer will allow drifting to draw the parts into position, but do not
enlarge the holes or distort the metal. Install drift pins and bolts
according to 513.20. Fill at least three-fourths of the holes with
completely tightened bolts in splices and connections subject to construction
loads during erection. Complete permanent fastening of steel truss
tension chord members before removing falsework.
Permanently fasten compression chord members after the span is released
sufficiently from the falsework to bring the
compression chord joints into full bearing. Properly regulate and
maintain elevations of panel points and ends of floor beams until the falsework is removed.
Do
not enlarge the holes of splices and connections between segments or elements
of main members without approval by the Office of Materials Management.
Adjust
structures to the correct alignment and to the marked bearing centerlines
before beginning permanent fastening. Do not permanently fasten cross
frames and lateral bracing in continuous beam or girder spans until completing
main connections in adjacent spans; however, install sufficient bracing to
maintain structural stability. For erection bolts used to fasten cross
frames, use not less than 5/8-inch (16 mm) diameter, and fully tighten bolts
according to 513.20.
Erect
end cross frames and end dams in a manner that ensures bearing parts remain in
bearing contact.
Permanently
fasten all intermediate cross frames before deck placement begins.
The
webs of primary members shall be plumb before deck placement begins.
513.27 Shop Coating. For steel surfaces specified to be coated according
to Item 514,
apply a prime coat in the shop.
513.28 Cleaning ASTM A 709/A 709M, Grade 50W (345W) Steel. Before the new steel is shipped, solvent clean,
where necessary, all surfaces of ASTM A 709/A 709M, and Grade 50W (345W) steel
that are to be left unpainted to remove all traces of asphalt cement, oil,
grease, diesel fuel deposits, chalk, paint marks, and other soluble
contaminants according to SSPC-SP 1 Solvent Cleaning.
QCP #1 and QCP #2 shall
apply according to Item 514.
Shop
blast unpainted Grade 50W material to SSPC-SP 6,
commercial blast. QCP #3 shall apply according
to Item 514.
After
placing superstructure concrete, clean, where necessary, the exterior surface
and bottom flanges of all fascia beams or girders that are
to be left unpainted to remove all traces of asphalt cement, oil, grease,
diesel fuel or petroleum deposits, concrete, and other contaminants.
Do
not use acid for cleaning.
513.29 Method of Measurement. The Department will measure Structural Steel Members
on a lump sum basis or by the number of pounds (kilograms).
If
payment is per pound (kilograms), submit weight computations to the Office of
Materials Management based upon the accepted shop drawings. Deduct waste
material, removed by burning, cutting, machining, holes, etc., but include groove
weld bevels. Include the weight of all permanent fasteners, shop fillet
welds, other metals and preformed bearing pads. Exclude the weight of
paint or galvanized coatings. Exclude thickness or weight of members
exceeding the plan requirements (due to overweight or other cause), unless
authorized by the Department. As an option, measure and record the weight
of structural members before painting in the presence of the inspector.
Use the following unit weights for computations.
|
lb/ft³ |
(kg/m³) |
Steel, cast steel, and deposited weld metal |
490 |
(7850) |
Cast iron |
450 |
(7210) |
Phosphor or leaded bronze |
550 |
(8810) |
Lead |
710 |
(11370) |
Preformed bearing pads |
710 |
(11370) |
The
Department will measure Welded Stud Shear Connectors by the number of each
installed and accepted.
513.30 Basis of Payment. If the fabricator’s proposed methods of assembly
with numerically controlled drilling or punching fail to produce specified
results and the Office of Materials Management directs the Contractor to
perform work, as according to 513.19 and 513.24, the Department will not pay for this work.
For
steel surfaces specified to be coated according to Item 514, the cost of
applying a prime coat in the shop is incidental to the bid for structural
steel.
The
Department will not pay for repairing or replacing members damaged by improper
handling, storing, transportation, or erection.
The
Department will pay for the accepted quantities at the contract prices as
follows:
Item
Unit
Description
513
Lump
Sum
Structural Steel Members, Level UF
513
Lump Sum
Structural Steel Members, Level 1
513
Lump
Sum
Structural Steel Members, Level 2
513
Lump
Sum
Structural Steel Members, Level 3
513
Lump
Sum
Structural Steel Members, Level 4
513
Lump
Sum
Structural Steel Members, Level 5
513
Lump
Sum
Structural Steel Members, Level 6
513
Pound (Kilogram)
Structural Steel Members, Level UF
513
Pound (Kilogram)
Structural Steel Members, Level 1
513
Pound (Kilogram)
Structural Steel Members, Level 2
513
Pound (Kilogram)
Structural Steel Members, Level 3
513
Pound (Kilogram)
Structural Steel Members, Level 4
513
Pound (Kilogram)
Structural Steel Members, Level 5
513
Pound (Kilogram)
Structural Steel Members, Level 6
513
Each
Welded Stud Shear Connectors