A seismic composite resilience model incorporating the recovery properties of serviceability and leakage for water distribution systems

Abstract

Post-earthquake restoration simulation process is an important step in conducting the seismic resilience analysis of water distribution systems (WDSs). Most of the existing simulation models neglect the isolation timing of pipelines with different damage degrees, tending to yield inaccurate seismic resilience assessment results. In addition, a single resilience index related to water supply capacity is usually considered in the existing studies, yet such individual indices may not fully represent the resilience characteristics of a WDS. To address these concerns, this study introduces a new restoration simulation model for WDSs based on key restoration events, which are defined as events changing the operation status (i.e., performance curve) of WDSs. Moreover, a seismic composite resilience model is proposed, by employing not only a water-supply-capacity parameter but also a leakage-related parameter as the resilience indices. Both proposed models are utilized to evaluate the seismic resilience and provide optimized restoration strategy for a WDS subjected to a moment magnitude 6.5 earthquake scenario. Comparative results demonstrate that the proposed models can result in desirable estimates of the performance curves of WDSs during restoration, and the leakage flow can be greatly reduced when the composite-resilience based restoration strategy is utilized. The models proposed could hopefully be utilized in engineering applications, such as guiding post-earthquake restorations of WDSs.