Seismic performance analysis of water-supply system considering interactions of water-electric systems

Water-supply system is one of the important lifeline systems, which plays an important role on the post-earthquake rescuing, reconstructing and rehabilitating. The paper presents a new modified methods to assess the seismic performance of water-supply system considering interactions between water-electric systems during earthquake. The interaction between water supply and electric system are estimated based on graph theory (GT) and network analysis (NA). With GT and NA, Both of water supply and electric systems are simulated as nodes and links, and the nodes are farther divided into simply nodes and complicated nodes, the former represents these nodes that their performance will not be affected by the performance of electric system, the latter stand for these nodes that their perfomance depends on the other elements in electric-power systems. The interactions between water supply and electric systems are considered in complicated nodes through the definition of several parameters based on the statistic analysis. The links are applied to describe the pipeline element and electric transmitting elements, and their performance levels are estimated considering the effect of the fault movement, ground displacement, and peak ground acceleration. Based on the reliability of nodes and links, the water-supply systemic reliability is calculated by use of GT and NA. Lastly, compared with seismic performance of water supply in one actual earthquake in China, one illustration is given to test the reliability of the proposed method in this paper.