中文摘要：

对5种不同高度的重力坝进行了地震作用下坝体一库水系统耦合计算，将所得结果与Westergaard公式解析解相比较发现，两种方法得到的动水压力结果沿坝高度上的分布有很大不同，流固耦合结果在坝面上有上部偏大，下部偏小的趋势；随着坝体高度的增加流固耦合模型的这种趋势越为明显，坝面上出现动水压力最大值的位置也逐渐升高。据此，对Westergaard公式做出修正，考虑到多方面因素对动水压力的影响，对原公式引入了坝体高度修正项、坝体弹性修正项、库底吸收修正项。修正的Westergaard公式解与流固耦合结果及以往文献的试验和计算结果吻合良好。

英文摘要：

Seismic analysis of gravity dams with five different heights in time domains was performed on the fluid-structure coupling model. Compared to fluid-structure coupling results, Westergaard solutions underestimate the hydrodynamic pressures in the upper part of the dam body, and overestimate in the lower part of the body. The overestimation is more significance with the increase of dam heights. The position where the maximal dynamic water pressure appears in the fluid-structure coupling model increases in height with the increase of the height of dams. On this basis, Westergaard equation was modified taking into account the influence of dam height, elasticity and reservoir bottom condition. The modified Westergaard formula solutions are quite coincident with the results of fluid-structure coupling models and other existing researches.