考虑大变形和排水条件时柱孔扩张问题统一解析  

UNIFIED ELASTIC PLASTIC SOLUTION FOR CYLINDRICAL CAVITY EXPANSION CONSIDERING LARGE STRAIN AND DRAINAGE CONDITION

作　　者：邹金锋[1,2] 吴亚中[3] 李亮[1] 彭建国[2] 张进华[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075 [2]湖南省交通规划勘察设计院,湖南长沙410008 [3]湖南省交通运输厅,湖南长沙410075

出　　处：《工程力学》2010年第6期1-7,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(50408020);高等学校博士点新教师基金项目(20090162120039);博士后科学基金项目(20090461021)

摘　　要：将柱孔周围土体中的应力分布分为弹性区和塑性区,在弹性区中采用小变形理论,在塑性区中采用大变形理论和统一强度准则。根据柱孔扩张问题排水条件时的应力平衡方程、应力和应变连续的边界条件,推导出考虑土体剪胀、大变形、排水条件和中主应力等因素的柱孔扩张问题塑性区半径和极限扩孔压力的理论解答,同时也获得了弹塑性区中的应力和应变场分布规律。理论计算结果与现场实测结果较为接近,初步说明该理论具有一定的工程应用价值。对比分析表明:扩孔压力和塑性区半径受土体剪胀的影响要比b值显著。In order to find the solutions of a cylindrical cavity expansion,the stress distribution due to the cylindrical cavity expansion in soil is considered as elastic and plastic regions.The deformation following a little deformation in the elastic zone and the large-deformation in the plastic zone is taken into consideration.On the bases of the stress equilibrium equation and continuous boundary condition of stress and deformation,the stress distribution in elastic and plastic regions,the terminal radius and cylindrical cavity expansion pressure are obtained.According to the comparison,the result of the present theory is very near to that of the Vesic＇s theories.The cavity expansion pressure and plastic radius affected by dilation is more than parameter of b.

关 键 词：大变形 剪胀 扩孔半径 极限扩孔压力 弹塑性 

分 类 号：TU433[建筑科学—岩土工程]