摘要
借助于多功能真三轴流固耦合试验系统,基于深部初始高地应力状态还原思路,对砂岩进行了不同应力路径、不同模拟深度下的真三轴正交力学试验,获得了真三轴不同工况下砂岩变形全过程应力-应变曲线,深入分析了砂岩在Z,Y,X三个方向上的渐进变形演化规律,表征了真三轴条件下砂岩渐进破坏力学行为演化特征,较好地反映了与之相对应的深部矿井巷道开挖后围岩的渐进变形演化特征及其渐进破坏力学机制。研究结果表明:①同一应力路径、不同模拟深度下的砂岩峰值强度随模拟深度的增加而不断增大,这表明深部效应对砂岩强度演化规律存在显著影响;②同一模拟深度、不同应力路径下的砂岩Z向主应变随Z向主应力的增大而不断增加,X向主应变却是随Z向主应力的增大而不断减小,这表明应力加载路径是影响砂岩X方向与Z方向渐进变形破坏机制的一大因素;③路径2与路径3下的砂岩Y向主应变均是随着模拟深度的增加而不断增大,而路径1下的砂岩Y向主应变却是随着模拟深度的增加呈现出先增大后减小的渐变规律,这说明应力卸载程度会显著影响砂岩Y方向的渐进变形特征。另外,不同应力路径下的砂岩X向主应变均是随着模拟深度的增加而不断增大,深部效应显著。
Based on the idea of deep initial high in-situ stress state reduction,the true triaxial orthogonal mechanics tests of sandstone under different stress paths and simulated depths were conducted by using the multifunctional true triaxial fluid-solid coupling test system.The stress-strain curves of sandstone under different true triaxial working conditions were obtained during the entire deformation process.The Z,Y and X direction progressive damage evolution laws of sandstone were analyzed.The progressive damage mechanical behavior evolution characteristics of sandstone under the true triaxial condition were characterized,which could better reflect the progressive deformation and failure mechanism of surrounding rock after excavation at deep mine roadway.The results show that the peak strength of sandstone increases with the increase of the simulation depth under different simulated depths and same stress path,which shows that the deep effect is significant for the strength evolution law of sandstone.The Z direction principal strain of sandstone increases with the increase of the Z direction principal stress under different stress paths and the same simulation depth,but the X direction principal strain decreases with the increase of the Z direction principal stress,which shows that the stress loading path is a major effected factor for the progressive deformation and failure mechanism of sandstone in X and Z directions.The Y direction principal strain of sandstone increases with the increase of the simulation depth under path 2 and path 3,while the Y direction principal strain of sandstone increasing firstly and followed by decreasing with the increase of the simulation depth under path 1,which shows that the stress unloading degree will significantly affect the Y direction progressive deformation characteristics of sandstone.In addition,the X direction principal strain of sandstone increases with the increase of the simulated depth under different stress paths,which shows that the deep effect is significant.
作者
张俊文
宋治祥
范文兵
丁露江
姚子祥
霍英昊
宿文桐
ZHANG Junwen;SONG Zhixiang;FAN Wenbing;DING Lujiang;YAO Zixiang;HUO Yinghao;SU Wentong(School of Energy and Mining Engineering,China University of Mining and Technology (Beijing),Beijing 100083,China;Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,China University of Mining and Technology (Beijing),Beijing 100083,China;National Demonstration Center for Experimental Safe Coal Mining and Geological Guarantee Education,China University of Mining and Technology (Beijing),Beijing 100083,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2019年第9期2700-2709,共10页
Journal of China Coal Society
基金
国家重点研发计划资助项目(2016YFC0600901,2018YFC0604703)
国家自然科学基金资助项目(51974319)
关键词
应力-应变
渐进破坏
砂岩
初始高地应力状态
力学行为
深部效应
stress-strain
progressive damage
sandstone
initial high in-situ stress state
mechanical behavior
deep effect
