侧向受荷板桩极限承载力的下限有限元分析  

Analysis of ultimate lateral resistance of sheet piles in clay by numerical lower bound method

作　　者：黄齐武[1] 黄茂松[1] 王贵和[2] 贾苍琴[2] 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]中国地质大学工程技术学院,北京100083

出　　处：《岩土工程学报》2007年第7期988-994,共7页Chinese Journal of Geotechnical Engineering

摘　　要：基于结构和平面应变单元,采用数值下限法分析结构–土体接触的稳定性问题。下限分析的求解借助锥形规划中原–对偶内点算法。提出了可以考虑轴力、剪力和力矩复合加载形式下的结构屈服形式;并以侧向受荷板桩为例,得出了水平力和力矩共同作用下的破坏包络线。结果显示:侧向受荷板桩的极限承载力H/(cL)是相对强度参数Mp/(cL2)的函数。该结果与Davis(1961)的刚性桩近似计算比较吻合。本文是下限有限元法首次采用结构和平面应变单元复合形式在深基础中的应用。The numerical lower bound limit analysis of structural and plane strain elements could be applied to analyze a wide range of stability problems involving soil-structure interaction. The lower bound analysis was formulated as second-order cone programming problem, solved by primal-dual interior point method, whose objective function was the maximization of the applied external load subjected to the constraints of a static admissibility. The failure of structural elements was allowed to occur under combined bending, shear and axial force, and the failure envelopes of free-head piles with combined horizontal load and moment were generated. It was shown clearly that the capacity of the laterally loaded piles H/（cL） was a function of the relative strength parameter Mpl（cL^2）, where H was the horizontal load applied at the top of the wall, L was the pile length, Mp was the plastic moment of the pile, and c was the undrained shear strength of clay. The results obtained for rigid piles agreed with approximate solutions of Davis （1961）. The first application of this combined formulation to analyze a laterally loaded pile embedded in a homogeneous clay layer was presented.

关 键 词：侧向受荷桩 黏性土 下限法 有限元法 二阶锥形规划 

分 类 号：TU473[建筑科学—结构工程]