Innovative HPS-70W Ford City Bridge Demonstration Project: Improved WeldabilityUsing Optimized Weld Metal Strength

摘要

In 1997, the Pennsylvania Department of Transportation proposed to the FederalHighway Administration the use of HPS-70W for a Demonstration Bridge Project that had two components. The first component focused on the design of an HPS-70W bridge for a specific site, Ford City, PA. The second component was to explore using nontraditional welding procedures to weld the butt joints in HPS-70W girders in the bridge. It is the second aspect of the demonstration project, the use of non-traditional welding procedures for HPS-70W girders in the Ford City Bridge, that is the focus of the report. The proposed innovation in welding procedures was to weld the HPS-70W flange splices in the bridge with traditional A588 steel welding consumables. This produces weldments in which the weld metal undermatches the strength of the base plates to a modest degree but the cost and reliability of the production process is optimized. This research was to demonstrate that the strength and fatigue resistance of these 'optimized' weld joints would be equivalent to ones welded using a higher strength weld metal that overmatches the strength of the HPS-70W base metal.