应力主轴旋转条件下各向异性云母砂变形的试验研究  

Experiment study on anisotropy sands subjected to rotation of principal stress axes

作　　者：于艺林[1] 童朝霞[2] 张建民[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]北京航空航天大学交通科学与工程学院,北京100191

出　　处：《世界地震工程》2010年第S1期85-89,共5页World Earthquake Engineering

基　　金：国家自然科学基金面上项目(50979046);国家自然科学基金青年基金项目(10902005)

摘　　要：实际工程中人工填土由于碾压的施工方法不同都存在不同程度的各向异性,在这些工程的不同阶段内部土体受力状态将发生变化,应力主轴会发生一定角度的偏转,导致诱发各向异性的产生。为了研究这种工况下,土体的变形特性,文中以固有各向异性较为明显的云母砂为研究对象,采用香港科技大学的自动控制空心圆柱扭剪仪进行了应力主轴连续旋转的循环扭剪试验,根据试验结果获得云母砂的诱发各向异性变形规律。Artificial filling earth is commonly anisotropic because of compaction.Practically,in different stages of construction,the stress status of soil unit inside structures is changed obviously.The deflection of principal stress axes induces anisotropy,which exerts a remarkable influence on the deformation characteristics of cohesionless soil.In this paper,tests on mica sand under the condition of cyclic rotation of principal stress axes are conducted with cylinder apparatus at Hong Kong University of Science and Technology.The test condition is that only principal stress axes rotated cyclically from 0° to 180° relative to vertical while effective principal stresses are kept constant.The deformation behavior of anisotropic sand is gained in detail.

关 键 词：各向异性 应力主轴旋转 云母砂 变形特性 

分 类 号：TU411.3[建筑科学—岩土工程]