Post-earthquake traffic load-carrying capacity of a RC deck-stiffened arch bridge damaged after an earthquake

Post-earthquake functionality of bridges is critical to ensure emergency response and maintaining lifeline connectivity. This study investigates the residual traffic load-carrying capacity of a reinforced concrete (RC) deck-stiffened arch bridge after seismic ground shaking. This type of RC bridge has been selected because it is frequently observed in the existing transportation infrastructure for its structural and aesthetic advantages. A comprehensive numerical framework was developed to assess the residual load-bearing capacity of the bridge after a design-level earthquake. A three-dimensional nonlinear finite element model was developed and validated against dynamic identification data. Spectrum-compatible ground motion records were selected and scaled according to Eurocode 8 and site-specific seismic hazard. Nonlinear time-history analysis was carried out to assess seismic performance and damage to the structural system. The presence of earthquake-damaged components was then considered into a subsequent robustness assessment of the bridge under traffic loads, based on incremental static (pushdown) analysis. Results reveal significant reductions in load-carrying capacity depending on the severity and location of seismic damage. The findings of this study offer insights into the robustness of RC deck-stiffened arch bridges, informing post-earthquake inspection, traffic management, and retrofit prioritization strategies.