水在兰州地区红层风化泥岩抗剪强度中的综合效应  

Effects of pore water in shear strength of weathered red mudstone in Lanzhou area,China

作　　者：何蕾[1] 文宝萍[1] 李慧[1] 

机构地区：[1]中国地质大学(北京)水资源与环境学院,北京100083

出　　处：《水文地质工程地质》2010年第3期48-52,共5页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目(40872182);中国地质大学(北京)2008年度大学生创新性实验计划项目资助

摘　　要：水与岩土相互作用是导致岩土抗剪强度降低的主要原因之一,这种宏观表象是地下水与岩土发生了一系列复杂的力学、物理和化学方面相互作用的综合结果。因此,查明水与岩土的相互作用模式是掌握岩土抗剪强度变化机理的关键所在。本文以兰州地区红层风化泥岩为对象,采用直剪试验方法,初步探讨了快剪条件下,孔隙水化学成分及pH改变时,该类风化泥岩抗剪强度的变化特点。结果显示,在快剪条件下,水在该类风化泥岩抗剪强度中的力学效应(孔隙水压力效应)与物理、化学效应同时存在,但力学效应明显强于物理效应和化学效应。地下水物理效应和化学效应的强弱与风化泥岩可溶盐含量及其化学成分、粘粒含量及其矿物成分有关。Water-soil /rock interaction is one of the key causes leading to reduction of shear strength of soil/rock. This is actually resulted from a series of complicated mechanical,physical and chemical interactions between pore water and soil/rock. Investigating these interactions is therefore a key to the understanding insight in variation of soil /rock＇s shear strength,which are functions of types of soil /rock and groundwater. In this paper,the interactions between the weathered red mudstone and pore water in Lanzhou area,China were preliminarily explored by means of direct shear testing. It was found that under the fast shearing condition,mechanical （pore water pressure）,physical and chemical effects function together making shear strength variation of the weathered red mudstone,and that mechanical effect is the strongest. The physical and chemical effects are closely associated with abundance of clay minerals and soluble salt within the weathered red mudstone.

关 键 词：兰州地区风化泥岩 抗剪强度 孔隙水压力 可溶盐溶解 阳离子交换 

分 类 号：TU459.4[建筑科学—岩土工程]