Performance of Water Storage Systems in the 2008 Wenchuan China Earthquake- A Field Study

The Wenchuan earthquake of May 12, 2008 in Sichuan Province in southwestern of China occurred as the result of movement on the Longmenshan fault or a tectonically related fault. The lifeline systems were damaged badly, with damage not seen in Chinese history. The main damages to water conservancy system were those of dams. This field study showed that the damaged reservoirs had a widespread distribution, and the damages of small-scale reservoirs were serious. Of 1996 earthquake-damaged reservoirs, dangerous situations included cracks on the dams (1425), collapse and settlement of dams (687), slide of dams (354), leaks of dams (428), damages of hoisting devices of dams (161), other damages of releasing devices, spillway, office room of dams (422), and many kinds of dangerous situations appeared simultaneously in more than 50% of the reservoirs. Performance of the two big dams is also discussed in this paper, i.e. Zipingpu Dam and Shapai Arch Dam. The damages to earth dams were mainly the longitudinal cracks on the top of the dams, sometimes prolonging the whole dam. There were transverse cracks individually, and serious one partially collapsed. In general many lessons could be learned from this event for our country as a seismic-prone country.