Evaluation of Weldments Incorporating Backing Materials
Fleet Technology Limited
M. Lalit Malik
This research developed a better understanding of the performance characteristics of fusible steel backings and nonfusible backing materials. In current steel bridge fabrication, a continuous steel bar is the most commonly used backing for groove welds. Fused-weld backing becomes an integral part of the structure and must be continuous to prevent weld cracking. The orientation of the backing relative to the direction of the applied stress is critically important. While careful adherence to existing codes should lead to acceptable performance, the essentials of good practice have not been widely understood.
The agency's final report includes user guides for design, fabrication, and inspection of one-sided welds on fused-backing bars. A welding procedure for one-sided nonfusible systems was also included.