多层加筋尾矿砂三轴压缩试验  

Triaxial compression test on multilayer reinforced tailing sand

作　　者：宁掌玄[1] 冯美生[1,2] 王凤江 王来贵[2] 

机构地区：[1]山西大同大学土木工程系,山西大同037003 [2]辽宁工程技术大学力学与工程学院,辽宁阜新123000 [3]秦皇岛冶金设计研究总院,河北秦皇岛066001

出　　处：《岩土力学》2010年第12期3784-3788,共5页Rock and Soil Mechanics

基　　金：国家自然科学基金面上项目(No.50374042);山西省科学技术发展计划基金项目(No.20080321068)

摘　　要：分别对含筋层数为1、2、4层的尾矿中砂和细砂进行三轴压缩试验,给出了不同增强层数下尾细中砂的邓肯-张模型参数。2层以下加筋时,土工织物对尾矿砂的横向变形约束作用较小,尾中细砂均表现为剪切破坏特征;在2～4层增强时,尾中细砂均表现为拉应力破坏特征;拉破坏条件下和剪切滑移破坏条件下,均发现加筋后的尾矿,凝聚力随加筋层数非线性增大,而内摩擦角基本不变。定义了增强效果系数,层数与该系数呈非线性关系。轴向应变小于5%～8%时,尾矿砂处于弹性变形阶段;轴向应变大于8%时,出现弹塑性耦合变形。Tiaxial compression tests are made with different number of geotexile. It gets the parameters of Duncan-chang model for reinforced sand with l, 2 and 4 geotexie layers. When 1 or 2 layers, the geotexile has a little restraint on the sand＇s lateral deformation and the failure mode is shear failure. When 3 or more layers, the failure mode is tensile failure. Under the two failure modes, the existence of reinforced material can influence the cohension force which is nonlinear increase with the layer＇s number, but not the inner friction angle. It defines the coefficient of the enhanced action which has a nonlinear rise according to the layer＇s number. When axial strain below 5%-8%, the sand is at the elastic distortion stage, but elasto-plastictity stage when above 8%.

关 键 词：尾矿砂 三轴试验 抗剪强度 土工织物 邓肯-张模型 

分 类 号：TU411[建筑科学—岩土工程]