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Microsoft Excel Version of the Table Below

AASHTO - Materials Engineer Survey
State conducting survey: Pennsylvania Department of Transportation (initiated May 8, 2009 - results summarized July 8, 2009)
Use of Gas Metal Arc Welding (GMAW) for Structural Steel (Bridge) Fabrication

State Does your State allow the use of GMAW for bridge fabrication (including FCM's)? If 'no' what is the reason(s)for the prohibition? If your State allows GMAW, which of the following transfer modes are permitted? If your state allows GMAW, are there any restrictions on welding parameters, shielding gases (combinations, percentages)? State Specifications or Requirements Person Responding
      a. Spray
b. Pulsed Spray
c. Globular
AL Yes Short circuit transfer is not recommended for the fabrication of bridge members but the transfer methods listed are permitted. All All welding parameters are governed by the Bridge Welding Code. D1.5 Bart Pickett
AR Yes, as allowed by D1.5   a. and c. (spray and globular) No See excerpt below table  
CA No Caltrans does not explicitly prohibit the use of GMAW for bridge fabrication, however all processes must be qualified (with the exception of SMAW) in accordance with D1.5 which cautions against the use of GMAW deposited using the short circuiting transfer process. Caltrans rarely is requested to accept GMAW due to the limited penetration when fabricating thicker sections of steel. Typically fabricators use SAW and FCAW with and without shielding gas. All (None of the referenced transfer modes are prohibited by Caltrans specifications. There are no restrictions, provided the procedure qualification is properly executed and witnessed by a Caltrans representative. There is no Caltrans specification explicitly describing the GMAW process as it relates to this discussion Tim Greutert
CT Yes, but this process has not been used in the past 20+ years   All of the above No D1.5 Ravi Chandran
FL FDOT allows the use of GMAW in bridge fabrication to include FCM's as allowed for by D1.5   All, as permitted by D1.5   D1.5 Steve Duke
GA GMAW is allowed, however all current fabricators are using GMAW only for tack welding with SAW being used as the final weld.   All of the above; short circuit transfer mode is prohibed Restrictions and limiatations as set forth in AWS D1.5 and PQR qualification testing. D1.5 Kevin Ledford
IL Yes, but all plate girder flange to web welds and shop welded splices in flanges or webs require automatic SAW onlly. This restriction effectively eliminates the use of GMAW from main member fabrication. One fabricator (Valmont) has recently started using a new GMAW process for seam welding high mas light tower shafts and we have approved their WPS. a. and c. (Spray and Globular) if and when permitted. We do not permit short circuit transfer mode. No special restrictions outside 4.14 and other sections in the Bridge Welding Code.   Christopher Mehuys
IA No. GMAW is not permitted for any main member welds Only permitted for tack welding a. only (spray). For tack welding only, as indicated.   James Berger
KS Yes   All, provided the company qualifies the process and welders. Per D1.5 and manufacturers recommendations.   Mike Popp
ME Yes   a. and b. (spray and pulsed spray) All parameters must maintain Spray or Pulsed spray transfer modes and the electrode/gas combinations must comply with AWS requirements. See excerpt below table  
MI GMAW is not specifically restricted - it is handled on a case by case basis. See specifications for more details. Restricted use is due to quality concerns and limited reliability of NDT and visual inspection. Not currently addressed by MI specifications, handled on a case by case basis.   See excerpt below table Jeff Weiller
MN MN DOT follows AWS D1.5 and therefore allows GMAW.   All are permitted, but require WPS approval No, must be used in accordance with D1.5 and an approved and qualified WPS D1.5 Barry Glassman
MO No Missouri permits GMAW for ancillary products (as defined in AWS D1.5) and for tack welds that will be thoroughly removed by the final weld. a. spray only   See excerpt below table Kent Nelson
NV Allowed but seldom used by our fabricators   All, but pulsed spray is typically used   D1.5 Todd Stefonowicz
NH No - We do not allow GMAW on primary members, but do allow it for secondary members and ancillary products. Historical - probably based on concerns regarding some of the fabricator's and equipment ability to positively control and maintain the transfer mode. All, as permitted by D1.5   See excerpt below table  
NM Yes - As governed by the Bridge Welding Code and Structural Welding Code.   All, as governed by the Bridge Welding Code. All, as governed by the Bridge Welding Code.   Timothy Mars
NY           Paul Rimmer
NC Yes - But web to flange welds must be by the Submerged Arc Welding process only   All No   Steven Walton
ND Yes - limited Web to flange welds must be welded using the automatic submerged arc welding process Per D1.5. GMAW-SS is not recommended   Section 616.03 D of our specifications Larry Schwartz
OH Yes, We follow D1.5. For FCM work only metal cored electrodes may be used per Section 12.5.1.   All - Care is taken with Globular transfer to ensure the weld doesnot turn into short circuit transfer. As described in D1.5   Jeff Chandler
SC Yes   a. and b. (spray and pulsed spray) SCDOT specs for GMAW are governed by D1.5



Mike Koon
TX Yes No restrictions on the use of GMAW other than those built into D1.5. This means that the only prohibited transfer mode is GMAW-SS. All   D1.5 Heather Gilmer
UT Yes and No. FCM would be restricted to GMAW with metal cored electrodes per D1.5 GMAW-S (short circuiting) is prohibited by D1.5 unless it has written approval by the Engineer. All Welding parameters for ancillary products would be recommended by the manufacturer. Primary members would be based on the results of the PQR. Our specifications does not address GMAW; it would refer to the requirements of D1.5. We currently have a fabricator using GMAW in fabrication of steel bridges. Jeremy Price
WI No Concerns regarding fusion. SAW is specifically required for butt and web to flange welds. We do allow FCAW for stiffener welds. GMAW is permitted for overhead sign structures, however we pay attention to the weld penetration concerns for these structures. N/A     Craig Werhle
Ministry of Transportation of Ontario   The industry has not yet requested that we approve GMAW procedures for welding bridge components. To date, welding procedures submitted for approval were SMAW, FCAW and SAW.       John Torontali

Number of States Responding: 25

Arkansas State Specifications or Requirements

807.26 Welding. (a) General. Welding of steel structures shall be accomplished by the electric arc process according to the ANSI/AASHTO/AWS D1.5 Bridge Welding Code, except as modified herein.
Welding shall be done by certified welders or certified welding operators approved by the Engineer, except that shop or field applied stud shear connectors welded using automatically timed stud welding equipment shall be accomplished by operators qualified according to Section 7 of the ANSI/AASHTO/AWS D1.5 Bridge Welding Code.
The Engineer will consider a welder/welder operator qualified if (1) the requirements of the standard qualification procedure of Section 5 of the ANSI/AASHTO/AWS D1.5 Bridge Welding Code are met, or (2) the Contractor provides a copy of the individual welder.s certified test report issued by an agency or authority on the Department.s Qualified Products List and the Contractor provides a certified statement of qualification for each welder stating that the welder has been doing satisfactory welding of the required type within the six month period prior to beginning work on the subject project. The certified statement of qualification will not be required during the six month period following a welder.s initial testing at a QPL listed agency.
The certified test report issued by the agency or authority recognized by the Department shall contain the name of the welder/welder operator, the name and title of the person who conducted the examination, the kind of specimens, the position of welds, the results of the tests, and the date of examination. Re-examination/re-certification will be required if welding of the required type has not been performed in the six month period prior to beginning work on the subject project.
In lieu of a certification for each project, the fabrication shop may submit an updated list of qualified welders/welder operators annually to the Materials Engineer. Addendum or additions to this list, along with the appropriate welder/welder operator certification, shall be submitted in a timely manner.
The approval and use of consumable welding materials shall be according to the Department’s Manual of Field Sampling and Testing Procedures.
(b) Modification of Structural Welding Code. The following changes and modifications to the ANSI/AASHTO/AWS D1.5 Bridge Welding Code shall be made:
(1) Subparagraph 1.3.2 is modified to include:
Electroslag welding shall not be used as a welding process on bridge structures.
(2) Subparagraph 3.2.1 is expanded to include:
Surfaces on which flange-to-web welds are made shall be cleaned in the immediate weld area by power wire wheel brushing, grinding, or other methods approved by the Engineer.
(3) Section 6, Part B, Radiographic Testing of Groove Welds in Butt Joints is expanded to include:
Edge blocks shall be used when radiographing butt welds greater than 1/2" (12 mm) thickness. The edge blocks shall have a length sufficient to extend beyond each side of the weld centerline for a minimum distance equal to the weld thickness, but no less than 2" (50 mm), and shall have a thickness equal to or greater than the thickness of the weld. The minimum width of the edge blocks shall be equal to half the weld thickness, but not less than 1" (25 mm). The edge blocks shall be centered on the weld with a snug fit against the plate being radiographed, allowing no more than 1/16" (1.5 mm) gap. Edge blocks shall be made of radiographically clean steel and the surface shall have a finish of 0.12 mils (3 μm) or smoother.
(4) Subparagraph 6.7.1 is modified as follows:
All complete joint penetration groove welds in butt joints in main members shall be examined by radiographic testing, except as provided in (2)(d). 807 779
(5) Subparagraph is amended as follows:
Twenty-five percent of each joint subject to compression or shear.
(6) Section 7, Stud Welding-Inspection Requirements is expanded to include:
A minimum of 5% but not less than 5 studs on each member shall be tested by being struck with a hammer and bent 15° off vertical. Additionally, any stud that by visual inspection does not show a full 360° weld, has been repaired by welding, or has an abnormal reduction in height due to welding shall be tested in the same manner. Where applicable, the direction of bending shall be opposite to the lack of weld. Studs that crack either in the weld or the shank after bending shall be replaced.
The remaining studs not subjected to the bend test shall be struck forcibly with a hammer. Any stud that does not yield a solid ringing sound shall be tested according to the above prescribed procedure.
The Engineer may select additional studs to be subjected to the bend test specified above. A visual inspection of the studs and welds shall be made by the Engineer prior to placement of the concrete deck slab. Any damage that may have occurred during shipment and erection shall be satisfactorily repaired.
All tests on studs shall be performed by the Contractor in the presence of an authorized representative of the Department.
If, during the progress of the work, inspection and testing indicates that the studs are unsatisfactory, the Contractor shall be required, at no cost to the Department, to make such necessary changes in welding procedure, welding equipment, and/or type of studs as necessary to secure satisfactory results.

Maine State Specifications or Requirements

504.28 Welding AASHTO M 270M/M 270 (ASTM A 709/A 709M),Gr. 250, Gr. 345, Gr. 345W Weld Procedure Specifications (WPSs) for groove welds and multiple-pass fillet welds shall be qualified by Procedure Qualification Testing in accordance with the D1.5 Code. The electrical parameters shall be within the consumable manufacturer’s published recommendations.
Each side of complete joint penetration welds, once begun, shall be welded to completion without interruption or a delay between passes except as necessary to maintain interpass temperature requirements. When backgouging is required, the groove and 75 mm [3 in] on either side of the groove shall be preheated to 51 C [125 F] immediately before the resumption of welding.
Single-pass fillet welds may be qualified by a Fillet Weld Soundness Test performed in accordance with the D1.5 Code as modified herein. The “T” test shall be performed by welding the smallest fillet weld to be used in production on one side and the largest fillet weld used in production on the other side of the “T”. The test specimens shall be macroetch tested in accordance with the requirements of Section 5 of the D1.5 Code. Acceptance and re-testing, if required, shall be in accordance with Section 5 of the D1.5 Code.
The minimum heat input for single-pass fillet welds during testing and production shall be 1.4 kilojoules/mm [35 kilojoules/in].
504.29 Welding AASHTO M 270M/M 270 (ASTM A 709/A 709M) HPS 345W (HPS 50W) and HPS 485W (HPS 70W) Steel Consumables shall be handled and stored in accordance with Subsections 12.6.5, and 12.6.6 of the D1.5 Code.
Filler metals for joining HPS 345W (HPS 50W) to HPS 345W (HPS 50W) or Grade 345W (Grade 50W) base metal shall meet the requirements of Table 4.1 or Table 4.2 of the D1.5 Code for Grade 345W (Grade 50W) steel.
Filler metals for welding HPS 485W (HPS 70W) base metal shall meet the following requirements:
Unless otherwise specified on the Plans, filler metals for fillet welds joining HPS 485W (HPS 70W) to HPS 485W (HPS 70W), HPS 345W (HPS 50W) or Grade 345W (Grade 50W) shall meet the matching filler metal requirements of Table 4.1 of the D1.5 Code for Grade 345W (Grade 50W) steel (H8 maximum).
Single-pass fillet welds joining HPS 485W (HPS 70W) to HPS 345W (HPS 50W) or Grade 345W (Grade 50W) steel shall meet the requirements of Section 4.1.5 of the D1.5 Code.
Single-pass fillet welds need not meet the requirements for exposed bare application.

Michigan State Specifications or Requirements

C&T:SJC 1 of 4 C&T:APPR:JAR:EMB:07-19-02
a. Description. This work consists of furnishing and fabricating structural steel according to the Fracture Control Plan (FCP) in the American Welding Society (AWS) AASHTO/AWS D1.5M/D1.5:2002 Bridge Welding Code and as stated herein. The FCP applies to steel for the flanges and webs of main load carrying members and other members as designated on the plans as Fracture Critical Members (FCM). This specification does not apply to fracture critical pins and hangers. All material requirements for pins and hangers shall be according to the standard specifications. In general, all work shall be done according to Division 707 of the standard specifications, AWS D1.5:2002 Bridge Welding Code, and the Special Provision for Structural Steel and Aluminum Construction. The requirements of this FCP shall supersede and are in addition to requirements specified elsewhere for structural steel.
b. Fabricating Fracture Critical Members (FCM). AWS Section 12. AASHTO/AWS Fracture
Control Plan (FCP) for Nonredundant Members.
AWS 12.4.5 Add the following to the paragraph:
The supplementary requirements of AASHTO M270 (ASTM A709) for fracture critical impact tests are required for zone 2. The Charpy test pieces shall be coded with respect to heat/plate number and that code shall be recorded on the mill-test report of the steel supplier with the test result. If requested by the Engineer, the broken pieces from each test (three specimens, six halves) shall be packaged and forwarded to the Michigan Department of Transportation, Construction and Technology Division.
AWS Add the following to the paragraph:
Electrodes for Shielded Metal Arc Welding shall be E7018.
AWS 12.7.5 Delete this section.
AWS 12.8.2 Add the following to the paragraph:
The Engineer shall witness all welding and test plates shall be submitted to the Department for machining and testing. Any reference to requalification on an annual basis shall be deleted.
AWS 12.14 Add the following to the paragraph:
C&T:SJC 2 of 4 07-19-02
The maximum interpass temperature for butt welding on fracture critical members shall not exceed 550 bF and for all other types of welding shall not exceed 650 bF. This includes all repair welding.
AWS Table 12.2 Delete Note 2. GMAW shall not be used on FCM’s.
AWS Add the following to the paragraph:
The minimum post heat time for production and repair welds shall be one hour.
AWS Add the following to the paragraph:
Repair drawings shall contain two lines for the Inspector's signature. Signature on the first line shall indicate the Inspector has examined the discontinuity(s) and agrees that the repair drawings accurately describe the discontinuity(s). When repairs are completed, signature on the second line shall indicate acceptance of the completed repair and the specified nondestructive tests. Discontinuities shall be drawn as they appear from visual inspection and NDT.
AWS 12.17.6 Add the following to the section:
The repair procedures shall include the welding procedure specification. Procedures qualified by test for the fabrication need not be qualified by test for the specific method of repair unless otherwise ordered by the Engineer.
(14) If stress relief heat treatment is required, it shall be completely described. Tests shall be performed to determine the effect of the heat treatment on both weld and base metal properties before the procedure is approved. Final acceptance NDT shall be performed after stress relief is complete.
(15) Repairs in tension butt welds shall be examined by ultrasonic (UT) and radiographic (RT) test methods. Repairs to all other groove welds shall be examined by UT. Fillet weld repairs shall be examined by MT. RT shall conform to Section 6 and may be performed as soon as the weldment has cooled to ambient temperature. UT shall also conform to Section 6 and MT shall conform to ASTM E709. Final acceptance testing by MT and UT shall not be performed until the steel weldments have been cooled to ambient temperature for at least the elapsed time indicated as follows:
Thickness Minimum Time
2 inches or less . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4 hours
over 2 inches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 8 hours
All repair welding and nondestructive testing shall be performed as described in the approved
repair procedure.
Approved critical repair procedures shall be retained as part of the project records.
C&T:SJC 3 of 4 07-19-02
AWS 12.17.6 (3) Add the following to the paragraph:
All air carbon-arc gouged and oxygen-cut surfaces that form a boundary for a repair weld shall be ground to form a smooth, bright surface. Oxygen gouging shall not be permitted in the repair of FCM’s.
AWS 12.18 Add this section to the code:
The Owner reserves the right to perform random nondestructive QA tests of welds, whether or not previously found acceptable by QC. Such testing will generally be by UT. If a weld is found to contain rejectable indications in QA then the following NDT shall be performed by and at the expense of the Fabricator: Two consecutive welds of the same type preceding the defective weld shall be tested. If any two consecutive welds are found by QC to contain rejectable indications, four consecutive welds made to the same welding requirements shall be tested by QC. All such testing shall be witnessed and verified by QA. All rejectable indications disclosed shall be repaired and reinspected by UT at the Fabricator's expense.
The QA witnessing and verification of QC testing will be carried out in a timely manner, so as not to interfere with production.
The Fabricator/Erector shall maintain documentation of all visual and nondestructive inspection for timely review and confirmation by the Engineer. Two copies of all documentation shall be submitted to the Engineer upon completion of the project.
AWS 12.19 Add this section to the code:
For welding procedure qualification, the test plate shall be according to the AASHTO Guide Specifications for Fracture Critical Steel Bridge Members with the following applying to the notes for Figure 1:
Delete notes 1, 3, 4 and 7 in the AASHTO guide specifications and replace them with the following:
1. "T" is equal to the maximum thickness to be welded, except as provided herein. When the thickness to welded exceeds 2 inches, "T" shall be the maximum depth of bevel, or 2 inches, whichever is the greater amount. The minimum thickness test plate shall be 1 inch in the event that the maximum thickness to be welded is less than 1 inch.
3. The minimum preheat and interpass temperature shall be according to AWS D1.5:2002, Table 12.4.
4. Welding procedure test plates shall be witnessed by the Engineer. Test plates shall be sent to the Department for machining and testing.
7. The reduced section tension specimen shall be according to Figure 5.10 of AWS D1.5:2002 except that "T" is equal to the test plate thickness.
C&T:SJC 4 of 4 07-19-02 03SP707(B)
c. Measurement and Payment. The completed work as measured for FRACTURE CRITICAL MEMBERS will be paid for according to the Standard Specification pay item Structural Steel, Furnishing and Fabricating. Payment for Structural Steel, Furnished and Fabricating includes all costs associated with furnishing and fabricating structural steel according to the requirements stated herein, the plans, and other specifications.

Missouri State Specifications or Requirements

The gas metal arc welding process shall not be used on any structural components of bridges. Approved gas metal arc processes may be used for incidental, non-structural components as may be specifically approved by the engineer. Tack welding with an approved gas metal arc process will be permitted for joints that will subsequently be welded using an approved submerged arc automatic welding process.

New Hampshire State Specifications or Requirements

Section 550- Structural Steel
3.6.3 Welding Processes. Main members. Welding of main load-carrying members and attachments (3.1.5) shall be performed using only submerged arc (SAW) and shielded metal arc processes (SMAW). Submerged arc welding. All principal welds on main members shall be made with the submerged arc process, including all welding of butt splices, flange-to-web welds, connection or stiffener plates to webs, and attaching cover plates. Shielded Metal Arc Welding. The use of the manual shielded metal-arc process shall be limited to welding connection plates to rolled beams, welding bridge shoes, repairs, tack welding, joints under 2 ft (600 mm) in length, minor detail attachments, and other limited welding applications where the use of submerged arc welding equipment is impractical because of limited access or the isolated location and short length of welds involved. Shielded metal arc welding may be used for submerged arc weld repairs. Only low hydrogen electrodes will be allowed. Proper electrode storage must be strictly adhered to according to the AASHTO Welding Specifications. Flux cored arc welding. The flux cored arc welding process (FCAW) may be used for members which are not main load-carrying members, such as bridge shoes, cross frames, diaphragms, steel bridge rail, steel light poles, scuppers, expansion joints, and approved secondary material, unless directed otherwise. Gas metal arc welding. The gas metal arc welding process (GMAW) may be used for welding the products listed in, unless directed otherwise. Electroslag (ESW) and electrogas (EGW) welding processes is not permitted.

New Mexico State Specifications or Requirements

This Work consists of fabricating, providing, erecting, and coating Structural Steel.
Structural Steel includes forged or cast steel, bolts, tie rods, other ferrous or nonferrous Materials, and miscellaneous steel.
The term “miscellaneous steel” refers to items such as:
1. Drop inlet grates and frames,
2. Safety grates,
3. Pedestrian rail, and
4. Cattle guard grates.
541.2.1 Structural Steel
Provide Structural Steel in accordance with AASHTO M 270, Grade 36, unless otherwise designated in the Contract. Provide steel for anchor bolts, sole plates, minor Bridge components, inlet grates, and cattle guards in accordance with AASHTO M 183.
541.2.1.1 Impact Testing Requirements for Non-Fracture-Critical Structures
For Materials requiring impact testing, do not weld repair the base metal at the producing mill. The Department will consider Structures to be non-fracture-critical, unless otherwise designated in the Contract. Fabricate the following in accordance with AASHTO M 270, Table 10 when subject to tensile stresses:
1. Wide flange beams used as main load carrying members;
2. Flanges, and web plates used in plate girders;
3. Flange cover plates;
4. Flange and web splice plates; and
5. Other components designated in the Contract.
Conduct Charpy V-notch (CVN) impact “H” or “P” frequency testing in accordance with AASHTO T 243.
Ensure that Structural Steel meets requirements for minimum service temperatures as described for Zone 2 of the AASHTO’s Standard Specifications for Highway Bridges (–1 °F–30 °F).
Conduct plate-frequency testing instead of hat-lot testing for plate Material thicker than 1 1/2 in.
541.2.1.2 Impact Testing Requirements for Fracture-Critical Bridge Components
The Contract will specify the CVN requirements for fracture-critical Bridge components.
541.2.2 Shear Connector Studs
Provide shear connector studs fabricated from cold-drawn bars, grades 1015, 1018, or 1020, either semi-killed or fully-killed in accordance with AASHTO M 169.
If using flux-retaining caps, use the low carbon grade steel for the caps that is suitable for welding and in accordance with ASTM A 109. Produce the finish by cold drawing, cold rolling, or machining.
Ensure stud tensile properties are in accordance with Table 541.2.2:1, “Tensile Properties of Shear Connector Studs,” as determined by tests of bar stock (after drawing) or finished studs, in accordance with ASTM A 370.
Table 541.2.2:1
Tensile Properties of Shear Connector Studs
Minimum requirement
Tensile strength
60,000 psi
Yield strength @ 0.2% offset
50,000 psi
Elongation in 2 in
Reduction of area
541.2.3 Bearing Pads
Obtain Department approval for impregnated fabric pads used beneath Bridge bearings.
Section 541: Steel Structures Page 1
541.2.4 Aluminum
Provide aluminum and aluminum alloy Materials in accordance with ASTM aluminum alloy designation and in accordance with the Plans.
541.2.5 Bolts
Provide high-strength bolts in accordance with Section 542, “High-Strength Bolts.” Provide other bolts in accordance with ASTM A 307, Grade A.
541.2.5.1 Unfinished Bolts
Provide unfinished ASTM A 307 bolts. Thread bolts so that not more than two threads are within the grip of the connected parts. Use bolts that will extend beyond the nut at least two threads, but not more than 1/2 in.
541.2.6 Structural Steel Coating
Provide coated Structural Steel in accordance with Table 541.2.6:1, “Coating of Structural Steel.”
Table 541.2.6:1
Coating of Structural Steel
Coating requirement
Structural Steel for steel Bridges
Section 544, “Protective Coating of New Structural Steel”
Structural Steel for concrete Bridges
Section 544, “Protective Coating of New Structural Steel” or Section 545, “Protective Coating of Miscellaneous Structural Steel”
Structural Steel for miscellaneous Structures
Section 545, “Protective Coating of Miscellaneous Structural Steel”
Metal bridge railing
Section 545, “Protective Coating of Miscellaneous Structural Steel”
New exposed steel Bridge piling and similar applications
Section 545, “Protective Coating of Miscellaneous Structural Steel”
Recoating Bridges
Section 546, “Recoating Structures”
If the Contract requires a galvanized coating, coat steel after fabrication in accordance with AASHTO M 111.
541.3.1 Applicable Codes and Documents
Fabricate and erect steel Structures in accordance with the current edition of the following codes and documents:
1. AASHTO/AWS D1,5 – Bridge Welding Code;
2. AASHTO/AWS D1,1 – Structural Welding Code;
3. AWS D1.4 – Reinforcing Steel Code;
4. The following AASHTO/NSBA Steel Collaboration documents:
4.1. S 2.1 Steel Bridge Fabrication Guide Specification
4.2. S 4.1 Steel Bridge Fabrication QC/QA Guide Specification
4.3. S 10.1 Steel Bridge Erection Guide Specification
4.4. G 1.1 Shop Drawing Review / Approval Guidelines
4.5. G 1.3 Shop Detail Drawing Presentation Guidelines
4.6. G 12.1 Guidelines for design for Constructability
Although the AASHTO/AWS Steel Collaboration documents are titled “Guidelines” or “Guide Specifications”, consider them to have the same importance and standing as a code or a specification. If the content of the collaboration documents appears permissive with words such as “should”, “could”, “may”, etc, consider the content to be a requirement unless otherwise approved by the Department.
In the event of a conflict between a referenced code and this specification, this specification will take precedence.
Section 541: Steel Structures Page 2
541.3.2 Quality Control and Quality Assurance
Conduct QC and QA operations in accordance with AASHTO/NSBA Steel Bridge Collaboration S 4.1. For shops fabricating miscellaneous steel items, the Department may waive the requirement that the QC inspector be a certified welding inspector.
541.3.2.1 Submittals to the QA Inspector
The Department’s shop Inspectors will prepare inspection reports covering the Structural Steel fabrication. Provide six copies of the following items for inclusion in the inspection report:
Structural Steel MTRs;
1. Certificates of Compliance and other documentation for the protective coating;
2. The manufacturers Certificate of Compliance for welding consumables;
3. Weld procedures;
4. QC inspection reports; and
5. A general Certificate of Compliance for the fabricated product.
Submit Certificates of Compliance instead of MTRs for Materials subjected to minimal stress levels, such as sole plates, shoe plates, anchor bolts, and fill plates.
541.3.3 Shop and Erection Drawings
Prepare shop drawings in accordance with AASHTO/NSBA G 1.3, Shop Drawing Presentation Guidelines. The Department will review and approve shop drawings in accordance with AASHTO/NSBA G 1.1, Shop Drawing Review / Approval Guidelines. Submit 10 complete sets of shop and erection drawings for preliminary review to the Project Manager. Retain two additional complete sets.
541.3.3.1 Approval of Initial Submittal
The Department will review the preliminary drawings. The Department will return three sets of drawings stamped “Approved except as noted” to the Contractor.
541.3.3.2 Errors and Changes Requiring Re-submittal
If numerous drawing changes and corrections are needed, the Department will return three sets of marked-up drawings to the Contractor with a letter requesting corrections and re-submittal.
Make changes and corrections as noted on the marked-up drawings and re-submit nine sets of corrected drawings; retain two additional sets.
Do not fabricate Materials before receiving drawings stamped “Approved” or “Approved as Noted.” Mark non-approved drawings “VOID.”
Allow at least 30 Days for review and approval of final shop plans and re-submitted shop drawings.
541.3.4 Shop Drawings for Structural Steel Items Detailed on Standard Drawings
The Contractor may submit standardized shop drawings instead of project-specific drawings for Structural Steel items such as cattle guard grills and drop inlet grates.
Include the Fabricator’s name and address, drawing title, drawing number, drawing date, revision dates, and standard serial number on shop drawings.
The Department will retain an approved set of shop drawings in a permanent file. Do not make any changes to approved shop drawings. If changes are made, re-submit the drawings for approval.
Before fabrication, submit a letter of intent to fabricate to the Project Manager containing the following information:
1. Names of the Fabricator;
2. Project number;
3. Drawing number;
4. Number of pieces to be fabricated;
5. Expected date of manufacture.
Submit a detailed bill-of-material in accordance with AASHTO/NSBA Steel Bridge Collaboration G 1.1 with the letter of intent to fabricate, to supplement the standardized drawings.
Submit one copy of each standard drawing to the Project Manager and the State Bridge Engineer at least 7 Days before starting Work. Notify the State Bridge Engineer at least 5 Days before starting Work.
For steel items unique to a project, prepare and submit shop drawings.
541.3.5 Reserved
541.3.6 Fabrication
Ensure shop drawings fabricating Bridges, overhead sign supports, and other major steel Structures are certified in accordance with AASHTO/NSBA Steel Collaboration S 2.1, Steel Bridge Fabrication Guide Specification. The Department will not require certification for shops fabricating miscellaneous steel items, but the Department must inspect and approve these shops before fabrication.
Steel will be fabricated in the shop unless otherwise approved by the Department.
541.3.6.1 Attachment and Fit of Gussets and Stiffeners
Where welding of gusset plates, stiffeners or other secondary attachments to main structural members would otherwise result in intersections of welds, clip back the corners of the attachments 1 1/4 in minimum from the corner in each direction to avoid such intersections.
Terminate welds attaching secondary components to main members 1/4 in short of the end of the attachments.
If the Plans require bearing stiffeners “finished to bear,” mill or grind the ends and obtain an even bearing against the flange the stiffeners will bear on.
Section 541: Steel Structures Page 3
If the Plans require “tight fit” stiffeners, fit the stiffeners tight against the flange to exclude water after being coated.
541.3.6.2 Straightening of Flanges
At pier bearings, abutment bearings and splices, straighten girder or beam flanges perpendicular to the webs. At bearings, straighten flanges before fitting stiffeners. At splices, straighten flanges before coating and shipment. Do not cold bend.
541.3.6.3 Bearing Plates, Pins, and Rollers
541. Sole, Masonry, and Shoe Plates
Flatten the top and bottom surfaces of sole masonry and shoe plates to within ± 1/32 in.
Machine sole plate surfaces that will contact elastomeric bearing pads perpendicular to the direction of expansion.
Machine other expansion surfaces in the direction of expansion.
541. Pins and Rollers
Accurately turn pins and rollers to dimensions and ensure that they are smooth, straight, and free of flaws.
541. Pin Holes
Bore a 2 in diameter hole longitudinally through the center of pins with an 8 in diameter or larger.
Bore pinholes true to the specified diameter, smooth and straight, at right angles to the axis of the member and parallel with each other unless otherwise required. Produce the final surface with a finishing cut.
Do not vary the outside to outside distance of end holes in tension members and inside to inside distance of end holes in compression members by more than 1/32 in Bore holes in built-up members after shop assembly.
541. Threads
Ensure that bolt and pin threads are in accordance with Unified Standard Series UNC-ANSI B1.1, Class 2A for external threads and Class 2B for internal threads. Thread pin ends with a diameter of 1 3/8 in or greater with six threads per inch.
541. Surface Finish
Finish the surfaces of bearings, base plates, pins, rollers, and other bearing steel that will come into contact with each other or with concrete in accordance with ANSI B46.1, Surface Roughness, Waviness and Lay.
Section 541: Steel Structures Page 4
541.3.6.4 Connections
541. Welding
541. Welder Qualifications
Use annually certified welders or those who provide documentation demonstrating continuing experience in the process and are position qualified.
541. Testing of Complete Penetration Welds
Conduct nondestructive QC radiographic testing on complete penetration welds in accordance with AWS D1.5 or D1.1 (as applicable).
The Department may allow ultrasonic testing as a substitute for radiography. Submit an ultrasonic testing plan for approval at least 30 Days before the start of fabrication. Provide detailed information about the Fabricator’s previous experience with ultrasonic testing and resumes showing the training and experience of persons performing the testing. Do not use ultrasonic testing for cases described in Section of the Bridge Welding Code.
541. Bolted Connections
Bolt with high strength bolts in accordance with Section 542, “High-Strength Bolts.”
Make bolt holes 1/16 in larger than the nominal diameter of the connector, unless otherwise specified.
541. Gaps Between Ends of Abutting Members
Where the Contract requires abutting milled joints, ensure there are no gaps. Face the ends to provide a full and even bearing when assembled.
Where the Contract requires close joints, do not exceed 1/8 in between the ends of abutting members. Do not exceed 1/4 in between abutting ends of girders at splices.
541.3.6.5 Camber Verification
Verify girder camber during the laydown operation. Unless assembling girders in the horizontal position, meet the total camber dimensions less the deflections produced by the weight of the girder.
541.3.7 Erection Requirements
Erect the Structure in accordance with AASHTO/NSBA Steel Bridge Collaboration S 10.1, Steel Bridge Erection Guide Specification.
541.3.7.1 Acceptance Mark
The Department will stamp fabricated members at the fabrication facility upon acceptance. Do not use any piece that does not bear the acceptance stamp.
541.3.7.2 Placement of Bearings
Ensure that column bases and bearing devices bear fully and uniformly on Substructures. Do not place bearings on pier or abutment Bridge seat areas that are improperly finished or irregular. Grout to achieve uniform bearing only when the Contract allows grouting.
Place masonry plates and beam and girder span pedestals on impregnated fabric pads approved by the Project Manager at least 1/8 in thick.
541. Anchor Bolt Holes
Core drill anchor boltholes in accordance with Table 541., “Required Nominal Anchor Bolt Hole Diameters.”
Table 541.
Required Nominal Anchor Bolt Hole Diameters
Bolt diameter (in)
Hole diameter (in)
1 1/2
1 3/4
1 1/4
Set anchor bolts using non-shrink grout from the Department’s Approved Products List. Remove excess mortar after the grout has set. Ensure that anchor bolt washers and nuts bear evenly against the steel-bearing surface. Ensure anchor bolts at the expansion ends of spans allow the free movement of the span.
541. Welding Sole Plates to Girders
At expansion bearings, weld sole plates to girder flanges or shoe plates after placing the concrete deck.
Before welding, adjust sole plate position to compensate for temperature expansion.
541.3.7.3 Field Bolting
Install high strength bolts in accordance with Section 542, “High-Strength Bolts.”
Block main structural members to the desired camber before torquing the bolted splice connections.
For skewed steel Bridges with diaphragms perpendicular to the longitudinal centerline, finger tighten diaphragm attachment bolts before deck placement. Fully torque bolts after the deck slab is in place.
Following completion of the Superstructure and after priming, fill open holes in exterior beams and girders with button head bolts before final acceptance.
541.3.7.4 Field Welding
Section 541: Steel Structures Page 5
Employ a QC inspector to monitor field welding certified in accordance with AASHTO / NSBA Steel Bridge Collaboration S2.1.
Provide QC reports certifying that welds meet specification requirements following each welding operation. Include the following in the report:
1. Welder qualification;
2. Weld procedure;
3. Electrode storage;
4. Preheat requirements; and
5. Acceptability of completed welds.
541.3.7.5 Pilot and Driving Nuts
Use pilot and driving nuts in driving pins. Show details on the shop plans. Furnish one pilot and one driving nut for each size pin.
541.3.7.6 Removal of Lead-Paint Coated Steel Items
Do not reuse salvaged steel items from existing Structures. Dispose of them in accordance with Section 547, “Safety and Environmental Requirements for Painting Operations.”
If structural members are specified by a nominal unit weight, the Department will calculate weight based on the nominal weights and dimensions.
When structural members are not designated by a nominal unit weight, the Department will calculate weight using the unit weights listed in Table 541.4:1, “Metal Unit Weights for Measurement.”
The Department will deduct the weight of copes, cuts, bevels, and open holes from the gross weight. The Department will not make deductions for bolt holes.
Table 541.4:1
Metal Unit Weights For Measurement
Unit weight (lb/ft3)
Cast iron
541.4.1 Bolts
The Department will calculate the weight of fasteners, except for anchor bolts, using weights listed in Table 541.4.1:1, “Bolt Unit Weights for Measurement.”
Section 541: Steel Structures Page 6
Table 541.4.1:1
Bolt Unit Weights for Measurement
Bolt diameter (in)
High-strength bolts (lb/100)
A 307 bolts (lb/100)
The Department will not include the weld material weight or the coating weight.
Pay Item Pay Unit
Structural Steel for Concrete Bridges Pound
Structural Steel for Steel Bridges Pound
Structural Steel for Miscellaneous Structures Pound
541.5.1 Work Included in Payment
The following work and items will be considered as included in the payment for the main items and will not be measured or paid for separately:
A. Submittals; nondestructive testing; protective coatings; and
B. Additional weight of heavier sections provided solely for the Contractor’s convenience;
C. All incidentals necessary for the completion of the work.
Section 541: Steel Structures Page 7

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