西藏高地震区碾压混凝土重力坝抗震研究

Seismic Analysis of a Roller Compacted Concrete Gravity Dam in Xizang with High Seismic Intensity

西藏高原地区某水电站为二等大(2)型工程,坝型为碾压混凝土重力坝,坝址地震基本烈度为Ⅷ度,大坝抗震安全成为该工程的关键技术问题之一。为此,对重力坝抗震安全分析方法除采用材料力学悬臂梁法外,对受地基刚度影响较大的坝体下部以及断面突变、应力集中等问题难以完全反映的问题,采用了三维有限元法进行了抗震分析及安全评价,计算结果均表明坝体满足抗震设防要求。

A hydropower station in Xizang plateau area is a class II large(2)project,in which the water retaining structure is a roller compacted concrete gravity dam and the basic seismic intensity of the dam site is VIII.The seismic safety of the dam is one of the key technical issues of the project.Besides the traditional gravity method based on the cantilever beam principles,three-dimensional finite element method is adopted for the seismic analysis and safety evaluation of the dam,especially for the lower part of the dam that are greatly affected by the foundation stiffness and the sudden change locations in the dam section.The results show that the seismic resistance requirements of the dam are satisfied.