Study On Seismic Damage Assessment Of Urban Water Supply Pipe Network

As an important component in urban lifeline engineering, the urban water supply pipe network is essential for human being's living and working activity. Previous earthquake disasters have demonstrated that the urban water supply pipe network is vulnerable to earthquake, while the economic loss and secondary disasters caused by the damages of the water supply pipe network were quite serious. However most of the urban water supply pipe networks in China have not been passed through the normal seismic design, and while many cities may have suffered the risk of earthquake. So it is necessary to make a seismic damage assessment on water supply pipe network.This paper summarized and analyzed the seismic damages of water supply pipe networks during several typical earthquakes, including Haicheng Earthquake, Tangshan Earthquake, Hanshin Earthquake and Wenchuan Earthquake. Based on the previous study made by other researchers and the damage characteristics of water supply pipelines during the Wenchuan Earthquake, the damage patterns of water supply pipelines were discussed, and also the factors which influence the damages were classified.Probabilistic methods are usually used to assess seismic damage of the water supply pipe network, with considering the randomness of the earthquake effects on underground pipelines. In this study, methods of seismic damage assessment on underground water supply pipeline were introduced, including the theoretical method and the empirical methods in Japan and in USA, with their comparison in practical aspects. Generally speaking, theoretical method is relatively conservative, especially in the case that the diameter of pipe is small. Moreover, when it is used to evaluate the flexible pipes, the result differs much from the reality. However, the empirical method shows greater applicability and reliability for evaluating the seismic damage of the water supply pipe network. In this study, a seismic damage assessment on urban water supply pipe network in seismic area was carried out to proof the availability of JWWA method. The result indicated that the water supply pipe network performs well when seismic intensity is 8 degrees, and part of the pipe network will be damaged seriously when intensity rise to 10 degrees. It can be a reference for government to establish disaster prevention plan.