饱和非饱和土的位移土压力及非极限力学指标研究  

Research on Displacement-related Earth Pressure and Non-limiting Mechanical Parameters for Saturated and Unsaturated Soil

作　　者：李顺群[1,2,3] 高凌霞[2,4] 柴寿喜[1,3] 李珊珊[1] 

机构地区：[1]天津城市建设学院土木工程学院,天津300384 [2]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [3]天津城市建设学院天津市软土特性与工程环境重点实验室,天津300384 [4]大连民族学院土木建筑工程学院,辽宁大连116600

出　　处：《中国公路学报》2013年第2期26-33,共8页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51178290);冻土工程国家重点实验室开放基金项目(SKLFSE200906);教育部科学技术研究重点项目(210004);天津市自然科学基金项目(11JCYBJC02900);天津市科技支撑计划重大项目(11ZCZDSF04800)

摘　　要：为了客观评估非极限平衡条件下,土力学强度参数的发展变化规律,基于摩擦定律、土压力与位移的双曲线模型、饱和非饱和土的Mohr-Coulomb强度准则、非极限平衡土力学参数同步发挥的假设,采用应力路径分析方法,研究了非极限平衡条件下饱和非饱和土的位移土压力对应的应力状态,并给出了位移土压力依赖于非极限内摩擦角、粘聚力和吸力内摩擦角等参数的理论计算公式。研究结果表明:当挡土结构由K0状态发生向着土体的正向位移时,基于位移的土力学参数先随着位移的增大而减小,在减小至0后又随着位移的增大而逐步增大,直至被动极限平衡状态;当挡土结构由K0状态发生背向土体的负向位移时,基于位移的土力学参数随着位移的增大而逐步增大,直至主动极限平衡状态;该方法为进一步研究挡土结构的力学性能、工作状态、安全储备提供了理论基础。To obtain displacement-related parameters, namely, friction angle, cohesion and suction friction angle, the stress path analyzing method was employed to study the stress state of saturated and unsaturated soil for retaining structure. The friction law, the hyperbola formula between earth pressure and displacement, Mohr-Coulomb strength theory and its modified form respectively for saturated and unsaturated soil, and the proportional exertion assumption for the soil mechanics were used. The results show that the displacement-related parameters willdecrease to zero with the increase of displacement and then increase until reaching the passive limit value when the retaining structure continuously moves towards the slopes; however, these parameters will increase to the active limit value as the structure deviating the slope. The proposed method provides theoretic foundation for the further research on mechanics, working state and security of the retaining structures.

关 键 词：道路工程 饱和非饱和土 应力路径分析法 非极限平衡 位移土压力 

分 类 号：U416.14[交通运输工程—道路与铁道工程]