基于概率的混凝土重力坝地震反应分析  

Probability-based seismic response analysis of concrete gravity dams

作　　者：寇立夯[1] 金峰[1] 王进廷[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水力发电学报》2009年第5期23-28,共6页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(90510018;90715041)

摘　　要：引入基于概率意义的分析方法,对地震反应分析中由于地面运动记录的不确定带来的结构反应不确定问题进了研究,并结合地震危险性分析的成果,得到了重力坝地震反应的超越概率。分析中首先选取一定数量的强震记录,在不同的地震烈度下对结构进行非线性分析。继而对分析得到的工程反应参数引入对数正态分布假设,通过回归分析得到其统计信息,并结合场地危险性曲线,得到年超越概率。最后对SAC/FEMA简化分析方法中各条假定对结果的影响进行了评价。对本文研究的重力坝而言,地震危险性曲线假定和工程反应参数均值变化规律假定带来的影响较小,而工程反应参数标准差假定会带来显著影响。A procedure to account the uncertainty of seismic response assessment due to the uncertainty in the characteristics of ground motions is presented. The mean annual probability of exceedance of gravity dams is computed from a series of deterministic response analysis with three loading intensity levels. The lognormal probability for the occurrence of engineering demand parameter is assumed and regression analyses are conducted on the parameters to obtain the conditional probability distribution. The results are combined with probabilistic estimates of seismic loading in order to estimate the mean annual probability of exceedance of various engineering demand parameters. The effects of various simplifying assumptions made in SAC/FEMA procedure are evaluated and discussed. It is concluded that more attention should be paled on the assumption about variation of dispersion.

关 键 词：水工结构 重力坝 地震分析 概率分析 性能设计 

分 类 号：TV31[水利工程—水工结构工程]