Simulation and Experiment on Repair Welding Maintenance of Orthotropic Steel Deck Fatigue Failure

ABSTRACT Based on the engineering background of the Hong Kong‐Zhuhai‐Macao Bridge (HZM Bridge), the fatigue characteristics and operation and maintenance strategies of orthotropic steel decks (OSD) were systematically studied through finite element simulation and high‐cycle fatigue (HCF) tests. A finite element model of the OSD segment is established to analyze the influence of unfavorable loading positions of longitudinal and transverse wheel loads on the stress distribution of U‐rib‐to‐deck weld ( U d ), U‐rib butt weld ( U b ), and U‐rib‐to‐diaphragm weld ( U rd ) and determine the fatigue dangerous position of welds. The critical crack size of welded components is predicted based on the Failure Assessment Diagram (FAD) method. The HCF testing showed that the fatigue life was reduced by 60% and 30% after toe and deck repair, respectively. Combined with the Paris' law and the damage equivalent coefficient method, the maintenance intervals for toe and deck repairs are 3 and 5.4 years, respectively.