Fatigue behavior of welded joints in orthotropic steel decks considering interaction of surface-embedded cracks
Yuan Luo,Yanpeng Wang,Xiaofan Liu,Fanghuai Chen,Haiping Zhang,Xinhui Xiao,Naiwei Lu
Abstract
Multiple cracks frequently observed in welded connection of orthotropic steel bridge decks, highlighting the need for a systematic understanding of their co-evolution mechanisms. This study investigates the interaction of coexisting surface and embedded cracks using the numerical simulations via Abaqus–FRANC3D. The stress fields of both crack types are analyzed under coplanar and non-coplanar conditions. Furthermore, the effects of crack spacing, embedded crack aspect ratio, and depth on stress intensity factors, crack propagates rates, and fatigue life are system atically evaluated. Results indicate that the relative positioning of cracks significantly affects fatigue behavior: coplanar configurations accelerate crack propagation, while non-coplanar configurations shield it. Key parameters, including initial crack spacing, embedded crack depth, and aspect ratio of the embedded crack all affect the fatigue life of welded joints. It is worth noting that under coplanar conditions, increased crack spacing accelerates propagation and signifi cantly shortens fatigue life. In contrast, under non-coplanar conditions, greater spacing enhances the shielding of the embedded crack, leading to earlier crack arrest. These findings offer valuable insights into the interaction mechanisms of multiple cracks and contribute to the improved lifecycle management of welded structures.
