高面板堆石坝地震响应比较——基于新、旧《水电工程水工建筑物抗震设计规范》

Comparison of seismic responses of concrete faced rockfill dam under excitation from design response spectra in new and old codes

《水电工程水工建筑物抗震设计规范》(NB 35047—2015)在《水工建筑物抗震设计规范》(DL 5073—2000)基础上,对标准设计反应谱曲线进行了修订。本文以某实际工程为背景,通过对250 m高典型面板坝进行二维有限元动力计算,对比分析了分别在新、旧规范谱人工地震波作用下,面板坝的频响特性及动力响应的差异。研究结果表明,在新规范谱人工地震波作用下坝体瞬时动位移、面板瞬时动应力、坝体总惯性力(最大加速度)、震后坝体永久变形以及面板震后应力等响应分量均较旧规范谱人工地震波作用有所增加,且坝坡的局部稳定性有所降低。据此,期望工程界关注新规范人工地震波作用下面板坝抗震安全性可能降低,并建议必要时对已建或在建工程进行抗震复核。

In 2015 the old code Specification for seismic design of hydraulic structures was revised into a new code, Code for seismic design of hydraulic structures ofhydropowerprojects. In this study, we have investigated dynamic responses and anti-seismic stability of a typical concrete faced rockfill dam （CFRD） of 250 m high under two types of seismic excitation formulated according to the new and old codes separately, to examine the differences caused by the two excitations. Our FEM results indicate that relative to the old code, the dynamic responses to the seismic waves designed by the new code are increased considerably and the local stability of dam slope is lowered accordingly. Thus we suggest more attention to these differences and a safety re-check on the built dams when it is possible.