Seismic resilience of simply supported bridges subjected to subduction earthquakes

Abstract

Seismic resilience is essential for maintaining the functionality and safety of transportation infrastructure, especially in areas prone to subduction earthquakes. Simply supported bridges, which constitute a significant portion of highway networks, are particularly susceptible to damage caused by seismic events, often resulting in connectivity disruptions and expensive repairs. This study assesses the impact of various failure mechanisms on the seismic resilience of these structures, considering insights from the 2010 Maule earthquake in Chile. Fourteen bridge models were analyzed and designed according to the pre- and post-2010 Chilean seismic design code. Nonlinear dynamic simulations were performed using OpenSees, incorporating soil-structure interaction effects to capture realistic response behaviors. Fragility curves were developed for multiple damage states, and a resilience assessment framework was applied to quantify functionality loss and recovery time. Results evince that bridges designed under the updated seismic code exhibit lower probabilities of severe damage and faster recovery times, primarily due to improved detailing and increased structural capacity. These findings emphasize the necessity of incorporating performance-based seismic design principles that account for the interplay between failure mechanisms, repairability, and long-term functionality.