scope:

These Specifications shall govern vehicular steel bridge fabrication. This work shall consist of furnishing and fabricating steel structures and structural steel portions of other structures in accordance with these Specifications and the contract documents.

Details of design which are permitted to be selected by the Fabricator or Contractor shall conform to the provisions of the current AASHTO LRFD Bridge Design Specifications (BDS). All numbered references herein to specific Articles in the BDS shall refer to the 9^th Edition.

Fabrication and welding, in addition to the requirements of these Specifications, shall conform to the provisions of the current AASHTO/AWS D1.5M/D1.5 Bridge Welding Code (D1.5M/D1.5).

Primary members or portions thereof designated in the contract documents as fracture critical members (FCMs) or system redundant mmbers (SRMs) shall conform to the provisions of Clause 12 of the current D1.5M/D1.5.

Coatings shall be considered outside the scope of these Specifications. Fabrication of pedestrian bridges, non-bridge structures or components such as expansion joints, bearings, or tubular members shall also be considered outside the scope of this specification.

The primary objective of these Specifications is to achieve quality and value in the fabrication of vehicular steel bridges and to help standardize vehicular steel bridge fabrication across the nation.

Historically, state Departments of Transportation (DOTs) have written their fabrication specifications based on AASHTO standards and their own individual experiences. Though this approach has worked reasonably well, many owners and fabricators recognized that all would benefit from a common specification because:

• Variations among projects in the shop would be minimized because fabricators would not need different practices, procedures, and operations for each owner, and minimizing variation improves quality and reduces errors.

• Economy in bridge fabrication would improve because fabricators would not have to change their methods and production variables from owner to owner.

• Expertise in steel bridge fabrication could be shared among states, resulting in a well-rounded, consistent fabrication standard.

• Owners would be able to share their resources, minimizing the effort each would otherwise have to expend to maintain a bridge fabrication specification.

These Specifications are based on existing state specifications, the AASHTO/NSBA Steel Bridge Collaboration S2.1, Steel Bridge Fabrication Guide Specification (S2.1); the AASHTO L RFD Bridge Construction Specifications (BCS); the AASHTO LRFD Bridge Design Specifications (BDS); and the AASHTO/AWS D1.5M/D1.5 Bridge Welding Code (D1.5M/D1.5). These Specifications defer to D1.5, the U.S. customary units specification in AASHTO/AWS D1.5M/D1.5, for specific welding requirements and for weld qualification testing requirements. The Owner is also encouraged to refer to the FHWA Welding Reference Manual for additional detailed information on welding. More information about AWS is available.

These Specifications assume that coating provisions are addressed in the referring Owner's standard specifications. For painting, the Owner is encouraged to refer to Steel Bridge Collaboration S8.1, Guide Specification for Application of Coating Systems with Zinc-Rich Primers to Steel Bridges. ASTM A123/A123M, Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products is a commonly specified standard for galvanizing. For thermal-sprayed coatings, the Owner is encouraged to refer to Steel Bridge Collaboration S8.2, Specification for Application of Thermal Spray Coating Systems to Steel Bridges.