高土石坝地震安全控制标准与极限抗震能力研究

基于土石坝震害调查和原型观测资料分析,针对高土石坝的坝坡稳定、坝体地震永久变形以及混凝土面板接缝位移3个影响高土石坝安全的主要因素,初步建议了相应的地震安全控制标准,并应用于高心墙堆石坝和面板堆石坝的极限抗震能力计算分析。结果表明：按规范设计的高土石坝具有较强的抗震能力,其极限抗震能力在0.50g以上,可抵抗9度以上地震而不致于出现灾难性后果;高土石坝的极限抗震能力与相应的地震安全控制标准密切相关,按照本文建议的标准,高心墙堆石坝坝坡稳定是其极限抗震能力的控制因素,高面板堆石坝面板周边缝安全是其极限抗震能力的控制因素。

Safety criteria and limit resistance capacity of high earth-rock dams subjected to earthquakes

By investigating and analyzing the earthquake damage performance and the in-situ observations of earth-rock dams, a series of criteria to control the safety of high earth-rock dams subjected to earthquakes are proposed in terms of three main influencing factors including slope stability, permanent deformation of the dam and deformation of peripheral joints. These criteria are used to study the limit earthquake-resistant capacity of a typical earth-core rockfill dam and a concrete faced rockfill dam, respectively. It is found that high earth-rock dams can resist strong earthquakes. The limit earthquake-resistant capacity of the two cases is as high as 0.5g, which means that the two dams can perform well without catastrophic subsequences even attacked by an earthquake with degree of nine. Furthermore, the limit earthquake-resistant capacity of high earth-rock dams largely depends on the safety criteria. The most important factor to control the safety of an earth-core rockfill dam under earthquakes is the slope stability while the deformation of the peripheral joint is the control factor for the safety of concrete faced rockfill dams.