Framework for Seismic Damage and Renewal Cost Analysis of Buried Water Pipelines

Abstract

Buried water pipelines suffer extensive damages when subjected to earthquake loading. Probable seismic damage of buried pipelines is typically estimated based on empirical analyses, where the effects of corrosion deterioration are often neglected. Corrosion-induced deterioration weakens the pipeline resistance capacity, which in turn significantly reduces the seismic reliability of water distribution systems (WDS). Improved seismic damage estimation of buried water pipelines needs to consider the effect of corrosion on their seismic performance to assist with the development of an effective and efficient renewal strategy. Hence, the first part of this study improves a current US guideline on seismic repair rate (RR) estimation, based on the observed effects of corrosion on pipeline damages during a recent earthquake (2014 Napa earthquake). Then, a renewal strategy is proposed that addresses the vulnerability of pipelines from the topological viewpoint in addition to the condition index and failure impact index commonly used in practice decisions. In addition, water distribution networks are often large and complex, which leads to considerable computational time and cost for seismic risk assessment. In this study, a computationally efficient methodology named SeismoPi is developed using Python-based open-source libraries for estimating the seismic damage of buried pipelines. The methodology is capable of performing scenario-based seismic damage analysis of complex buried water networks, identifying critical segments and system connectivity, and estimating the renewal cost. The method presents the interactive outputs on maps so that decision makers can easily visualize the results and identify the riskiest segments that need to be rehabilitated. SeismoPi assists decision makers in developing WDS renewable strategies that account for the effects of corrosion deterioration on their seismic performance. Applications of the proposed framework are demonstrated on a few small- to large-sized water distribution systems.