大理岩泥夹层剪切蠕变特性研究  

Study on Shear Creep Characteristic of Marble Clay Interlayer Masses

作　　者：李志敬[1] 周伟华[2] 朱珍德[3] 

机构地区：[1]黄河勘测规划设计有限公司岩土工程与材料科学研究院,河南郑州450008 [2]郑州经贸职业学院建筑工程系,河南郑州450044 [3]河海大学岩土工程科学研究所,江苏南京210098

出　　处：《人民黄河》2012年第12期130-132,135,共4页Yellow River

基　　金：国家自然科学基金资助项目(50539090)

摘　　要：针对锦屏二级水电站地下洞室群围岩含有大量节理面的实际情况,采用岩石剪切蠕变仪,对组成锦屏二级水电站地下洞室围岩的主要岩石之一大理岩,进行了大理岩泥夹层结构面剪切蠕变试验。结果表明:在正应力恒定情况下,当剪应力水平较低时,蠕变曲线出现衰减蠕变和稳态蠕变;当剪应力水平较高,大于其蠕变长期强度时,蠕变曲线出现衰减、稳态和加速蠕变3个阶段;大理岩泥夹层在整个剪切蠕变过程中,平均剪切蠕变速率与剪应力呈线性关系,稳态蠕变速率与剪应力呈指数关系;与瞬时剪切强度相比,长期强度有所降低,黏聚力对剪切蠕变的影响比摩擦系数要大;随着时间的延长,剪切蠕变模量经历了从衰减到逐渐稳定的过程。The subsurface rock masses of Jinping Second Stage Hydropower Station caves have with abundant joints. A shear creep experimental pro- granl was carried out on the marble clay interlayer masses, with respect to their shearing behaviors. A shear creep apparatus was employed to fulfill the program. The results show that in the normal stress constant conditions, creep curve appear attenuation creep curve and steady-state creep curve when the shear stress level is lower; creep curve appear the three creep phase including attenuation creep phase, steady-state creep phase and accelerated creep phase when the shear stress level is higher and greater than its creep long-term strength. On the process of shear creep experiment, the average shear creep rate .and shear stress of marble clay interlayer is linear relationship, the steady cre6p rate and shear stress of marble clay interlayer is index relationship. Compared with instant shear strength, long-term shear strength decrease, cohesion is more effective than friction coefficient in affecting shear creep behaviors. With the increase of time, shear creep modulus experience from attenuation to gradually stable process.

关 键 词：泥夹层 剪切蠕变 蠕变速率 蠕变模量 锦屏二级水电站 

分 类 号：TV16[水利工程] TG115.5[金属学及工艺—物理冶金]