Fatigue Life Assessment of Revised Cope-Hole Details in Steel Truss Bridges

Abstract

In recent years, various welded details with complex local structure, ambiguous fatigue performance have appeared in fully welded steel truss bridges, however, they are not covered in the current design specifications. In order to study the fatigue performance of revised cope-hole details, fatigue performance experiments were designed and carried out on three specimens of revised detail with the same dimensions but subjected to different stress amplitude. Local finite element model of the revised cope-hole detail was established for further stress analysis. The results of finite element analysis were basically consistent with the static test results at majority of measurement points. Based on the existing fatigue test data and fatigue strength of cope-hole details defined in Eurocode and JSSC design code, the fatigue performance of revised cope-hole details was evaluated. The S-N fitting curve with the failure probability of 2.3% was obtained from the fatigue experiment results. The fatigue stress amplitude was 59.5 MPa when fatigue loading cycle was 2 × 106. It can be concluded that the fatigue performance of revised cope-hole detail was better than that of previous welded detail, which indicated that the revised detail had a significant improvement.