一、引言混凝土重力坝在弱地震作用下,各坝段之间的横缝也许会发生滑动,但坝体整体作用仍较明显;而在强烈地震作用下,坝段之间可能开裂,产生滑动,形成单个坝段的振动。印度Koyna大坝在1967年12月11日Koyna地震时,缝面出现混凝土破裂和漏水就说明了这点。因此,取单个坝段进行地震反应分析是合适的。我们选取了三峡最高的溢流坝段作为典型坝段 I. INTRODUCTION Under the action of weak earthquake, the concrete gravity dam may slide transversely between the dam sections, but the overall effect of the dam body is still obvious. However, under the strong earthquake, the dam sections may crack and slip , Forming a single dam of the vibration. Koyna Dam, India This is evidenced by the concrete cracks and water leaks at the Koyna earthquake on December 11, 1967. Therefore, taking a single dam for seismic response analysis is appropriate. We selected the highest spillway section of the Three Gorges as a typical dam section