平面应变条件下非饱和土抗剪强度统一解及应用  

Unified solution of shear strength for unsaturated soil under plane strain condition and its application

作　　者：张常光[1,2] 胡云世[3] 赵均海[4] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092 [3]衢州学院,浙江衢州324000 [4]长安大学建筑工程学院,陕西西安710061

出　　处：《岩土工程学报》2011年第1期32-37,共6页Chinese Journal of Geotechnical Engineering

基　　金：陕西省自然科学基金项目(SJ08E204)

摘　　要：基于统一强度理论和非饱和土双应力状态变量抗剪强度,合理考虑中间主应力效应,推导了平面应变条件下非饱和土双应力状态变量抗剪强度统一解,进而考虑中间主应力、特别是基质吸力高低的不同影响,建立了非饱和土主动、被动土压力和任意侧压力系数下均适用的条形地基临界荷载解析解。本文解析解具有广泛的理论意义,根据实际工程具体情况,可进行多种选择。研究结果表明:在低基质吸力范围内,非饱和土被动土压力和条形地基临界荷载随着统一强度理论参数和基质吸力的增大而不断增加,主动土压力则相反;在高基质吸力范围内,被动土压力和临界荷载均逐渐减小并趋于稳定;超固结比对条形地基临界荷载的影响较小。Based on the unified strength theory and the shear strength of unsaturated soil in terms of two state stress variables,the unified solution of shear strength for unsaturated soil under the plane strain condition is derived by taking into consideration the effect of the intermediate principal stress rationally.Analytical solutions for unsaturated soil of the active earth pressure,the passive earth pressure and the critical bearing capacity for strip foundation suitable for any lateral pressure coefficient are presented by considering the intermediate principal stress,particularly different influences of high and low matric suctions.The analytical solutions obtained in this paper have very broad theoretical values.More choices can be made according to the actual engineering situations.The results show that in the low matric suction region,the passive earth pressure and the critical bearing capacity for strip foundation increase as the unified strength theory parameter and matric suction increase,while the active earth pressure decreases.In the high matric suction region,the passive earth pressure and the critical bearing capacity gradually decrease and reach some constants.The influence of over-consolidation ratio on the critical bearing capacity for strip foundation is less significant.

关 键 词：非饱和土 统一强度理论 土压力 临界荷载 高基质吸力 

分 类 号：TU432[建筑科学—岩土工程]