New Framework Integrates Structural Reliability and Resilience in Earthquake Engineering
Researchers have proposed a generalized performance-based earthquake engineering (PBEE) framework that integrates structural damage, recovery, and long-term resilience into a single continuous-time Markov chain model. Current PBEE methods treat post-earthquake recovery as a separate step and rely on assumptions that treat each seismic event as independent, which limits their ability to capture how repeated earthquakes affect structures over time. The new approach could improve life-cycle seismic risk assessments by revealing resilience gaps that conventional reliability metrics miss.
A preprint submitted to arXiv by Bruno Sudret and colleagues introduces a unified mathematical framework for assessing how buildings and infrastructure perform under repeated seismic loading over their lifetimes. Existing performance-based earthquake engineering methods typically model structural reliability and post-earthquake recovery as separate processes, relying on Poissonian assumptions that treat each earthquake event as independent and the structure as effectively 'renewed' after each one. The new framework embeds both damage accumulation and recovery dynamics directly into system state transitions using a continuous-time Markov chain governed by a single generator matrix. Time-dependent failure probabilities, reliability indices, and a resilience metric—defined as the expected fraction of operational time before collapse—are all derived from the same mathematical object, enabling consistent and efficient computation via the matrix's spectral properties. The methodology was demonstrated on a three-state illustrative example and then applied to two structural archetypes: a braced frame and a base-isolated building system. A key finding is that recovery dynamics can substantially influence long-term resilience even in cases where standard reliability measures show little sensitivity, suggesting that ignoring recovery in life-cycle assessments may lead to underestimating risk. The work argues for explicitly incorporating recovery into seismic performance standards and design practice.
What's missing
The study is a preprint and has not yet undergone peer review. The framework is demonstrated on simplified structural archetypes and a three-state example; validation against real-world earthquake damage and recovery data, or more complex multi-state structural systems, is not reported. The Markov chain formulation assumes state-transition rates are time-homogeneous, which may not capture time-varying hazard rates or non-stationary seismic environments. Computational scalability to large or highly heterogeneous structural portfolios is not assessed.
What different sources said
- arXiv physicsCenter
A generalized framework for performance-based earthquake engineering: integrated assessment of structural reliability and resilience
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