Seismic resilience assessment of pile-supported bridges in the permafrost considering temperature-induced degradation effect

Temperature-induced degradation of permafrost significantly affects the seismic performance of pile-supported bridges located in permafrost regions, increasing the risks of economic and environmental consequences. Seismic resilience assessment plays a pivotal role in disaster prevention and mitigation efforts. However, the seismic resilience assessment method for pile-supported bridges in permafrost regions remains inadequately studied, particularly when considering temperature-induced degradation. Here, we conducted a methodical evaluation of the seismic resilience of pile-supported bridges, incorporating the effects of temperature-induced degradation and using finite element simulation results. Initially, triaxial shear tests were conducted on island permafrost soil collected along the Tieli–Yichun High-Speed Railway at various temperatures. p-y curves for permafrost soil at different temperatures were constructed using scaling factors to model the interaction between soils and piles. Then, a typical prestressed concrete pile-supported bridge along the Tieli–Yichun High-Speed Railway was selected, and the corresponding 3D nonlinear finite element model was developed. In addition, we performed pushover analysis of the pile–soil interaction to define the boundary values for different damage states. Based on the computed results, the optimal measure of seismic motion intensity was selected based on relevance, efficiency, practicality, proficiency, and hazard computability. The seismic resilience of the pile-supported bridge, accounting for temperature-induced degradation, was developed and compared. The results indicated that temperature-induced permafrost degradation significantly affects the pile-supported bridge's damage probability, functionality loss, and seismic resilience.