动载扰动后花岗岩物理力学特性研究  

Physical and mechanical properties of granite after dynamic disturbance

作　　者：杨福见 胡大伟[1,2] 周辉 卢景景[1,2] 张帆 YANG Fujian;HU Dawei;ZHOU Hui;LU Jingjing;ZHANG Fan(State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China;University of Chinese Academy of Sciences, Beijing 100049, China;School of Civil Engineering and Architecture, Hubei University of Technology, Wuhan, Hubei 430068, China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学和工程国家重点实验室,湖北武汉430071 [2]中国科学院大学,北京100049 [3]湖北工业大学土木工程与建筑学院,湖北武汉430068

出　　处：《岩石力学与工程学报》2018年第6期1459-1467,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展计划(973)项目(2014CB046902);国家自然科学基金资助项目(51779252;51479193)~~

摘　　要：基于对动载扰动后的大部分岩体在一定时间内恢复原岩应力状态或承受因动载扰动而重新分布应力的认识,利用新提出的静动–静组合加载方式,开展一维动静组合加载前后花岗岩力学、渗透率、波速和声发射等特性的对比性试验,为研究深部工程岩体在动载扰动下物理力学特性的演化规律提供一种新的思路。研究结果表明:(1)动载扰动后,基于超声波速定义的损伤变量随着轴向静压的增加逐渐增大,随频率的增加先减小后增大,最大损伤程度可达16%。(2)岩样气体渗透率及泊松比整体大于未扰动岩样的试验结果,随轴向静压的增加逐渐增大,随频率的增加先减小后增大,对高轴压水平表现出较强的"敏感性"。(3)岩样强度及弹性模量总体小于未扰动岩样的试验结果,随轴向静压的增加逐渐减小,随频率的增加在不同轴压水平下呈现不同的结果。(4)动载后单轴压缩过程中能量释放与未扰动岩样相比缺少能量释放初期及能量释放潜伏期,直接进入了能量释放活跃期,该阶段持续时间延长,且结束时的相对应力及能量释放峰值对应的相对应力存在"滞后现象"。Most of the rock masses after dynamic disturbance return to the original state of stress or have the stress redistributed within a certain time period. One dimensional coupled dynamic and static loading tests were carried out under a new type of static and dynamic-static loading combinations to compare the characteristics of mechanical properties,permeability,wave velocity and acoustic emission of granite. The damage variable defined according to the ultrasonic velocity increases gradually with the increasing of the static axial pressure（ASP）,decreases first and then increases with the increasing of frequency. The maximum damage degree reaches 16%. The permeability and Poisson’s ratio of samples are larger than the results of undisturbed samples,increase with the increasing of ASP,and increase at first and then decrease with the increasing of frequency. Both show high sensitivity to the high ASP. The strength and elastic modulus are less than the results of undisturbed specimens,increase with the increasing of ASP,and vary differently at the different levels of ASP with the increasing of frequency. Compared with the energy release of undisturbed rock samples,the specimen after the dynamic loading in the uniaxial compression process have no initial and latent stages of energy release and enter directly into the active stage of energy release with the duration prolonged and a lag phenomenon exists in the relative stress at the end and the energy release peak.

关 键 词：岩石力学 动静组合加载 宏观力学 渗透率 波速 声发射 

分 类 号：TU458[建筑科学—岩土工程]