真三轴不同应力路径下深部砂岩力学特性  

Mechanical characteristics of deep sandstone under different true triaxial stress paths

作　　者：张俊文[1,2,3] 范文兵 宋治祥 霍英昊 丁露江 姚子祥 ZHANG Junwen;FAN Wenbing;SONG Zhixiang;HUO Yinghao;DING Lujiang;YAO Zixiang(State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;School of Energy and Mining Engineering,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)

机构地区：[1]中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室,北京100083 [2]中国矿业大学(北京)能源与矿业学院,北京100083 [3]中国矿业大学(北京)煤炭安全开采与地质保障国家级实验教学示范中心,北京100083

出　　处：《中国矿业大学学报》2021年第1期106-114,共9页Journal of China University of Mining & Technology

基　　金：国家重点研发计划项目(2016YFC0600901,2018YFC0604703);国家自然科学基金项目(52034009,51974319);中国矿业大学深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK1828)。

摘　　要：采用多功能真三轴流固耦合系统,对深部砂岩试件进行了不同模拟深度、不同应力路径下的还原初始应力试验,得到了相应工况下深部砂岩试件的全应力-应变曲线,分析了相应的变形及强度特性.结果表明:在还原σ_(z),σ_(y),σ_(x)过程中,σ_(z)-ε_(x),σz-ε_(z),σ_(z)-ε_(y)曲线出现了长度不一的“平台”特征;深部砂岩试件峰值强度随着模拟深度的增加而增大;通过引入压裂系数,得出了从初始应力状态点到峰值强度点对应的体积变形量仅占初始应力状态下体应变的10%~20%;不同应力路径下,相比于Drucker-Prager准则,Mogi-Coulomb准则更适合描述岩石的强度特性.By using multi-function true triaxial fluid-solid coupling system,the initial in-situ stress reduction tests under different simulated depths and stress paths were carried out for the deep sandstone,and the stress-strain curves of the deep sandstone under corresponding working conditions were obtained.The corresponding deformation characteristics and strength characteristics were analyzed.The results show that:In the process of restoringσ_(z),σ_(y),σ_(x),theσ_(z)-ε_(x),σ_(z)-ε_(z),σ_(z)-ε_(y)curves of deep sandstone has the characteristics of“platform”of different lengths;With the increase of simulation depth,the peak strength of deep sandstone increases;By introducing fracturing coefficient,the results show that the volume deformation from the initial in-situ stress state point to the peak strength point only accounts for 10%—20%of the volume strain of the initial stress state;Under different stress paths,compared with Drucker-Prager criterion,Mogi-Coulomb criterion is more suitable to describe the strength characteristics of rocks under different stress paths.

关 键 词：深部砂岩 真三轴试验 应力路径 力学特性 强度准则 

分 类 号：U[交通运输工程]