考虑上部结构作用的闸坝地基液化分析  

Liquefaction potential evaluation of dam foundation soil considering influence of overlying structures

作　　者：王刚[1,2] 魏星[3] 

机构地区：[1]雅砻江水电开发有限公司,成都610051 [2]重庆大学土木工程学院,重庆400044 [3]西南交通大学土木工程学院,成都610031

出　　处：《水力发电学报》2014年第4期220-226,共7页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金(51209179);国家973计划(2010CB732103);中央高校基本科研业务费专项资金(SWJTU12CX068)

摘　　要：基于液化判别的对比应力法和动力反应分析,对某闸坝工程进行了考虑上部结构作用的地基液化评价。复杂应力状态下砂土的液化判别条件是该分析方法的关键。采用有限元数值方法计算地基的静动应力场以反映上部结构与地基的静动力相互作用。通过详细的原位勘探和室内静动力试验,以得到地基土的静动力变形特性和不同初始应力状态下的抗液化应力比曲线。该方法可以给出地基抗液化安全系数的分布,比规范简化方法的液化判别结果更能合理地反应结构-地基系统的具体边界条件和力学特性的影响,能更具针对性地确定地基处理方案。A liquefaction evaluation procedure for the foundation soils of a sluice dam is presented in this paper. This procedure is a stress-based approach that compares earthquake-induced cyclic stresses with cyclic resistance of soil. Seismic responses are analyzed by using a 3D dam-foundation coupling FE model to estimate the earthquake-induced cyclic stresses in the foundation. Detailed laboratory monotonic and cyclic triaxial tests were conducted to evaluate the static and dynamic characteristics and the cyclic resistance against liquefaction of foundation soils. The procedure can give the distribution of liquefaction-resisting safety factor, and the results better reflect the effects of boundary conditions of a structure-foundation system and its characteristics on the liquefaction potential of foundation than the simplified method. Foundation improvement could be designed according to the results and the zone predicted by the presented method.

关 键 词：水工结构 液化 动力反应分析 闸坝 相互作用 

分 类 号：TU435[建筑科学—岩土工程] TU441[建筑科学—土工工程]