Experimental investigation of creep behavior of clastic rock in Xiangjiaba Hydropower Project

作     者：Yu Zhang Wei-ya Xu Jian-fu Shao Hai-bin Zhao Wei Wang 

作者机构：College of Pipeline and Civil Engineering China University of Petroleum Geotechnical Research Institute Hohai University Hunan Provincial Key Laboratory of Key Technology on Hydropower Development 

出 版 物：《Water Science and Engineering》 (水科学与水工程（英文版）)

年 卷 期：2015年第8卷第1期

页      面：55-62页

核心收录：

学科分类：08[工学] 0815[工学-水利工程] 081503[工学-水工结构工程] 

基　　金：supported by the National Natural Science Foundation of China(Grants No.51409261 and 11172090) the Natural Science Foundation of Shandong Province(Grants No.ZR2014EEQ014) the Applied Basic Research Programs of Qingdao City(Grant No.14-2-4-67-jch) 

主　　题：Rock mechanics Clastic rock Creep behavior Triaxial creep test Burgers creep model Xiangjiaba Hydropower Project 

摘      要：There are many fracture zones crossing the dam foundation of the Xiangjiaba Hydropower Project in southwestern China. Clastic rock is the main media of the fracture zone and has poor physical and mechanical properties. In order to investigate the creep behavior of clastic rock, triaxial creep tests were conducted using a rock servo-controlling rheological testing machine. The results show that the creep behavior of clastic rock is significant at a high level of deviatoric stress, and less time-dependent deformation occurs at high confining pressure. Based on the creep test results, the relationship between axial strain and time under different confining pressures was investigated, and the relationship between axial strain rate and deviatoric stress was also discussed. The strain rate increases rapidly, and the rock sample fails eventually under high deviatoric stress. Moreover, the creep failure mechanism under different confining pressures was analyzed. The main failure mechanism of clastic rock is plastic shear, accompanied by a significant compression and ductile dilatancy. On the other band, with the determined parameters, the Burgers creep model was used to fit the creep curves. The results indicate that the Burgers model can exactly describe the creep behavior of clastic rock in the Xiangjiaba Hydropower Project.