为获得高应力下具有剪切错动历史、延展规模大、组合结构和矿物构成多元化等特点的白鹤滩层间错动带强度值(黏聚力和内摩擦角),首先介绍了6种错动带试验研究,包括针对错动带泥化软层的环剪试验、高压直剪试验和三轴压缩试验,以及针对错动带复合体的直剪试验、三轴压缩试验和现场试验。综合分析不同试验对象和不同试验条件下获得的错动带强度值,归纳出了错动带黏聚力和内摩擦角与试验方式、加载的法向应力大小、试样特点及含水率之间的关系,并发现白鹤滩错动带强度特性具有典型的组合体结构效应、弱胶结效应、围压效应、水软化效应。在此基础上,提出"原状错动带强度"和"扰动错动带强度"两个概念,并进一步讨论了白鹤滩厂址区原状的和扰动的层间错动带强度参数取值问题。其研究结果可为白鹤滩地下洞室群的安全设计和深部地下工程中同类泥化夹层的力学参数取值提供参考。
For the purpose of getting the strength value of Baihetan interlayer shear belt with the characters of dislocation history,large scale spread,assembled multiplex structure,multiplex mineral,etc.,six kinds of tests are introduced,including ring shear test,high stress direct shear test and triaxial compression test for soft argillization layer,and straight shear test,triaxial compression test and in-situ shear test for multiplex shear belt.Based on the testing data of above six tests,the relationships between strength of shear belt and loading mode,value of normal stress,character of specimen and moisture content are summed up.The strength properties of shear belt,include assembled structure effect,thin cementation effect,confining pressure effect and water soften effect are found.What’ more,the conceptions of "original strength" and "disturbed strength" of interlayer shear belt are put forward,which have different cohesive strengths and friction angles.These cognitions can provide useful cures for supporting design of Baihetan underground caverns and study of similar argillization layer in deep underground engineering.