二滩拱坝地震响应的动力模型试验研究

二滩双曲拱坝的动力模型试验在大型模拟地震振动台上进行。研究了在实际地震波作用下,坝体、水库和地基的相互作用影响,坝体抗震安全度,动水压力分布和拱坝在强烈地震下的破坏机理。研究结果表明:1.高拱坝的最大动应力是拱应力,位于上游坝顶中间部位。下游坝顶中间部位和2/3坝高部位以及坝踵是抗震薄弱部位。2.紧靠拱坝上游面的山体形状对坝面动水压力值的影响较大,故对于坝前地形复杂的水库,应模拟一倍坝高长的自然地形。3.满库时,拱坝前几阶固有频率对库水位的微小变化非常敏感。4.拱坝在强烈地震下的破坏在瞬间完成,主要是中上部的脆性开裂。

Dynamic Model Test for Seismic Response of Ertan Arch Dam

The dynamic model tests of Ertan double curvature arch dam is conducted on thelarge scale analog seismic vibrator. Under the real seismic waves, the interaction of dambody, reservoir and foundation, the anti-seism safety of dam body, hydrodynamic pressuredistribution and the damage mechanism of arch dam by strong seism are studied. Studiedshow; 1. The maximum dynamic stress of high arch dam is arch stress located in the middlepart of dam crest upstream. The middle part of dam crest downstream,2/3 dam height partand dam heel are the weak parts of anti-seism. 2. Since the mountain shape close to upstreamof arch dam has great influence on hydrodynamic pressure value, natural topographyof double dam height should be simulated for the reservoir with complex topography in frontof the dam. 3. When the reservoir is full, the natural frequency of stages in front of the archdam is very sensitive to the minor change of reservoir level. 4. Damages of the arch dam bystrong seism completed instantly is mainly due to brittle fracture in the middle and upperparts.