黄土地区第三系红色黏土岩蠕变特性研究  

STUDY OF CREEP CHARACTERISTIC OF TERTIARY ARGILLACEOUS ROCK IN LOESS AREA

作　　者：王中文[1] 袁志强[1] 李滨[2] 朱杰兵[3] 汪华斌[1] 

机构地区：[1]华中科技大学土木工程与力学学院,湖北武汉430074 [2]中国地质科学院地质力学研究所,北京100081 [3]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010

出　　处：《岩石力学与工程学报》2010年第A02期4008-4015,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(40772170;40872192);"十一五"国家科技支撑计划重点项目(2006BAC04B05)

摘　　要：以宝鸡刘家泉滑坡体内具代表性的三门组黏土岩为研究对象,进行黏土岩物理性质分析和室内流变、快剪试验。试验结果表明,研究区域黏土岩矿物成分以伊利石–蒙脱石混层矿物为主,黏土岩具有成岩时间短、强度低、胶结程度差等特点,且具有明显的膨胀性。此外,室内流变剪切强度参数与快速剪切强度参数相比,摩擦因数f降低了66%,黏聚力c值降低了80%。剪切流变试验结果表明,位移随时间的增加,黏土岩表现为低应力条件下非线性黏弹性和高应力条件下线性黏塑性特性,具有良好的流变变形特征。在岩石流变结果分析的基础上,通过五元件广义Kelvin模型和Bingham模型串联代表黏土岩的流变模型,能较好地反映出黏土岩的流变特性,且计算曲线与试验结果能较好地拟合出蠕变的衰减蠕变阶段和等速蠕变阶段,并应用遗传算法对黏土岩流变本构模型进行参数辨识,拟合结果与试验结果能够很好地吻合。Time-dependent behavior of rock mass is one of the important factors influencing the deformation and long-term stability of slope. The large scale incised-rock landslide in the loess area is progressively deformed under the influence of deadweight and groundwater,etc. This kind of landslides was finally formed after creeping, cracking and shearing,on the basis of the previous surface due to the preliminary creeping behavior of argillaceous rock. It aims to study the creeping behavior of argillaceous rock after the analysis of physico-mechanical properties,in which the Liujiaquan landslide was taken for example in Jintai District of Baoji. The analysis of clay minerals in argillaceous rock shows that the rock is mainly composed of mixed-layer illite-montmorillonite and illite. It also noted that the rock is formed in the latest period of geological time,and characterized with lower strength,light cementation and expansibility. Compared with the results of quick shear test,it is found that the value of friction coefficient reduces by 66% and the value of cohesion by 80% in the process of rheological shearing. Meanwhile,the displacement increases with time,and the deformation behavior is identified to be nonlinear viscoelastic in low loading and linear viscoplastic in high loading. It can be concluded that the creeping behavior is the main property of argillaceous rock in the process of preliminary landsliding in the studied area. In addition,the generalized Kelvin and Bingham models were combined to describe the rheological properties. The calculation curves of the model and experimental points could well fit the decay creep stage and steady state creep stage of the argillaceous rock. Hence,the suitability of selected models was proved. Finally,the parameters of rheological constitutive model of argillaceous rock were identified using genetic algorithm. Comparing the curves fitted by genetic algorithm with experimental data,it is found that the fitting results and the test results are matched very well. The genetic

关 键 词：岩石力学 黏土岩 蠕变试验 流变模型 参数识别 遗传算法 

分 类 号：TU45[建筑科学—岩土工程]