Seismic resilience and economic loss evaluation of mountainous reservoir bridges retrofitted with lead rubber bearings subjected to hydrodynamic effects

This study establishes a comprehensive analytical framework for evaluating seismic resilience and economic loss, accounting for water levels, seismic isolation systems, and explicitly integrating time-dependent underwater rehabilitation processes during post-earthquake recovery. A case study was conducted on an existing highway bridge located in a mountainous reservoir environment, where conventional elastomeric bearings (EBs) were proposed to be retrofitted with seismic-isolation lead rubber bearings (LRBs). A three-dimensional coupled mechanical-numerical model was developed, and nonlinear dynamic time history analysis was performed to assess the seismic vulnerability of the bridge and quantify the impact of LRBs on the seismic resilience and economic loss in the structure. The results indicate that LRBs significantly reduce bridge damage probabilities caused by hydrodynamic effects during seismic events. The mitigation efficiency exhibits a statistically significant positive correlation with water depth . Quantitative assessments reveal the dual benefits of LRBs: enhancing seismic resilience and reducing post-earthquake economic losses, with improvements in the seismic resilience indices ranging from 20.9%-49.8% and economic loss mitigation between 43% and 62% across analyzed hazard scenarios . The proposed risk-informed assessment framework integrates FEMA P-58 methodologies with seismic isolation and hydrodynamic interaction modeling, enabling quantitative evaluation of economic losses and seismic resilience for bridges in mountainous reservoir environments . Further studies on the applicability of these findings to various bridge types would be valuable.