石英砂岩蠕变力学特性及长期强度研究  

Study on Creep Mechanical Properties and Long-term Strength of Quartz Sandstone

作　　者：杨帅东 谭维佳[2] 方应学 YANG Shuaidong;TAN Weijia;FANG Yingxue(Pearl River Water Conservancy Institute,Guangzhou 510611,Guangdong,China;College of Geological Engineering and Survey,Chang an University,Xi an 710054,Shaanxi,China;Jiangsu Water Greening Engineering Co.,Ltd.,Nanjing 210029,Jiangsu,China)

机构地区：[1]珠江水利委员会珠江水利科学研究院,广东广州510611 [2]长安大学地质工程与测绘学院,陕西西安710054 [3]江苏水源绿化工程有限责任公司,江苏南京210029

出　　处：《水力发电》2021年第4期43-50,共8页Water Power

基　　金：国家重点基础研究发展计划(973计划)资助项目(2017YFD0800501)。

摘　　要：通过三轴压缩蠕变试验,分别以过渡蠕变法、等时应力-应变曲线法、稳态蠕变速率与应力关系法、残余应变法以及强度与破坏时间关系法研究石英砂岩的长期强度。结果表明,对于石英砂岩的长期强度,前4种方法得到的结果大体一致;过渡蠕变法、残余应变法只能根据应力梯度得到长期强度临界值,等时应力-应变曲线法取拐点的过程具有一定主观和随意性,稳态蠕变速率与应力关系法受岩石稳态蠕变发展程度影响,确定的长期强度略小于等时应力-应变曲线法;针对传统稳态蠕变速率与应力关系法的不足,通过同时在曲线左、右侧取切点交点的方式进行改进,确定石英砂岩在围压4、8 MPa和12 MPa下的长期强度分别为19.63、27.65 MPa和37.07 MPa,折减范围为33.4%~34.5%。Through triaxial compression creep test,the long-term strength of quartz sandstone is studied by transition creep method,isochronous stress-strain curve method,steady-state creep rate stress relationship method,residual strain method and strength failure time relationship method respectively.The results show that,(a)for the long-term strength of quartz sandstone,the results obtained by the first four methods are generally consistent;(b)the transition creep method and residual strain method can only obtain the long-term strength critical value according to the stress gradient,the isochronous stress-strain curve method is subjective and arbitrary,and the long-term strength values of quartz sandstone obtained by the steady-state creep rate and stress relationship method respectively are slightly less than that of isochronous stress-strain curve method as the two methods being influenced by the rock steady-state creep development degree;and(c)in view of the shortcomings of the traditional steady-state creep rate and stress relationship method,the method of taking the intersection point of shear points on the left and right sides of the curve is improved.The long-term strength of quartz sandstone under confining pressure of 4,8 MPa and 12 MPa is 19.63,27.65 MPa and 37.07 MPa respectively with the reduction range of 33.4%~34.5%.

关 键 词：岩石力学 石英砂岩 稳态蠕变 长期强度 加卸载 

分 类 号：TU452[建筑科学—岩土工程]