ABSTRACT Pile‐group‐supported highway bridges are highly vulnerable when subjected to the combined effects of scour and earthquakes, as damage typically occurs across multiple interdependent components, especially in pile groups. However, existing approaches to seismic resilience assessment often neglect damage correlation of different bridge components and their realistic recovery processes. This study proposes a pseudo‐copula‐enhanced cloud‐based (PC‐Cloud) fragility analysis method to quantify the joint damage probability of multiple components with consideration of their damage correlations, which can also compute individual components’ seismic fragility. Building on this, a high‐fidelity probabilistic methodology is developed for assessing the seismic resilience of pile‐group‐supported highway bridges with scour effects, accounting for bridge components’ damage correlations, recovery sequence and process, as well as associated uncertainties. Resilience is expressed through conditional exceedance probabilities, capturing both post‐earthquake bridge functionality loss and equivalent bridge downtime. The methodology is demonstrated on a benchmark pile‐group‐supported highway bridge. The damage state of pile groups is defined, considering plasticity development of all potential damage regions within the pile group. Results show that scour significantly amplifies seismic damage probability of pile groups, shifting the earthquake‐induced damage from pier to pile group. Consequently, scour increases the likelihood of earthquake‐induced bridge downtime and post‐earthquake functionality loss. The proposed methodology provides a computationally efficient and mathematically rigorous tool for assessing the resilience of highway bridges under multi‐hazard conditions. It also enables integration of seismic resilience outcomes into the current performance‑based earthquake engineering framework.
Zhou et al. (Wed,) studied this question.