饱和砂土不排水单调剪切特性试验研究——考虑剪切过程中变化的总主应力方向的影响  

Effect of Orientation of Principal Stress on the Undrained Behavior of Saturated Sand under Monotonic Shearing

作　　者：张振东[1,2] 栾茂田[1] 金丹[1] 许成顺[1,3] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室大连理工大学土木水利学院,辽宁大连116024 [2]淮海工学院土木工程学院,江苏连云港222005 [3]北京工业大学城市与工程安全减灾省部共建教育部重点实验室,北京100022

出　　处：《防灾减灾工程学报》2009年第6期604-609,共6页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(50579006);国家自然科学基金重点项目(50639010)资助

摘　　要：利用土工静力-动力液压三轴-扭转多功能剪切仪,针对相对密度Dr=30%的福建标准砂,进行了不排水条件下的单调剪切试验。在剪切过程中,控制平均固结应力和中主应力系数保持不变,而总主应力方向不固定。与剪切过程中总主应力方向固定不变条件下的单调剪切试验进行了对比分析。试验研究表明,当饱和砂土试样具有水平沉积面时,初始固结主应力方向与剪切方向的不同组合,导致单调剪切过程中总的主应力方向的不断变化,从而显著地影响着饱和砂土不排水单调剪切特性。总的主应力方向是影响饱和砂土不排水单调剪切特性的最根本原因。Using the soil static and dynamic universal triaxial and torsional shear apparatus, a series of undrained monotonic shear tests are performed for saturated Fujian standard sands with a relative density of 30%. The mean consolidation stress and the coefficients of the intermediate principal stress are invariable while the orientation of principal stress is variable in the proceeding of tests. By contrasting with the monotonic shear test results under the condition that the orientation of principal stress is invariable, it is concluded that when the saturated sand sample has horizontal sedimentary plane, the different combina- tions of initial orientation of major principal stress and direction of monotonic shearing make the actual orientation of major principal stress different during the shearing, which affecting the undrained monotonic shearing behavior of sand remarkably. The actual orientation of major principal stress is the most essential factor which affects the undrained monotonic shearing behavior of the saturated sand.

关 键 词：单调剪切 总主应力方向 孔隙水压力 各向异性 水平沉积面 

分 类 号：TU441.5[建筑科学—岩土工程]