拱坝地震动随机响应分析

将河谷地震动随机场半解析展开为正交函数随机过程及采用简化的地基模型，应用振型分解法可直接求得拱坝－地基－库水系统的各种随机响应及功率谱密度。本文方法不仅考虑地震动的空间随机性，山体放大作用及行波效应，而且考虑非比例阻尼的拱坝振型之间的相关性；地震动随机场只须分解一次，计算过程简单，是大型拱坝结构随机分析的一种有效方法。

RANDOM RESPONSE ANALYSIS OF ARCH DAM SUBJECT TO SEISMIC EXCITATIONS

A procedure is proposed to analyze the random response of arch dam subjected to spatially correlated seismic excitations. The earthquake ground field is expanded into a set of independent random processes. The developed massless foundation model is also taken into consideration. The proposed approach can deal with random correlative problems, canyon seismic amplification and wave-propagation effect problems, and even the dam-foundation- reservoir non-classic damping problems. An numerical example is provided to demonstrate the proposed procedure. It is shown that the procedure is very effective in random seismic analysis of large structures suds as dams.