基坑支护结构主动极限位移的影响因素分析  

Study on Influencing Factors for Active Limiting Displacement of Supporting Structure of Foundation Pit

作　　者：姚海明[1] 张雷[1] 周松 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]上海第二市政工程有限公司,上海200065

出　　处：《地下空间与工程学报》2005年第4期526-529,共4页Chinese Journal of Underground Space and Engineering

摘　　要：运用弹塑性有限元程序计算基坑支护结构和土体的应力状态,采用“人工参与”的优化法来研究当基坑支护结构偏离土体方向时使土体达到主动极限平衡时的主动极限位移。大量数值计算表明:主动极限位移随土层深度增加而增加,但到一定深度后其增量为零,主动极限位移与土的弹性模量成反比。在此基础上研究了上海软土地区基坑支护结构主动极限位移的近似公式,工程实测资料证实了该近似公式的有效性和实用性。Stresses in supporting structure and the retained soil in foundation pit are analyzed with elasto-plastic FEM, and the active limiting displacement of supporting structure was calculated with 'artificial participation' optimization. A large scale numerical calculation shows that the active limiting displacement is increasing with the depth of retained soil and the increment will be zero when the soil depth reaches some degree. The result also shows that the active limiting displacement is an inverse measure of the Young's modulus. An approximate formula of active limiting displacement of supporting structure in foundation pit is proposed for Shanghai soft soil. Furthermore, the in situ measured result shows the availability and applicability of the approximate formula.

关 键 词：基坑支护 主动极限位移 优化方法 

分 类 号：TU311.2[建筑科学—结构工程]