低渗透片麻岩渐进破裂过程中渗透规律研究  

Study on Permeability of Low Permeability Gneiss During Progressive Rupture

作　　者：王俊光[1] 金峤 梁冰[1] 曹强 李刚[2] WANG Junguang;JIN Qiao;LIANG Bing;CAO Qiang;LI Gang(Institute of Mechanics&Engineering,Liaoning Technical University,Fuxin 123000,China;School of Mines,Liaoning Technical University,Fuxin 123000,China)

机构地区：[1]辽宁工程技术大学力学与工程学院,辽宁阜新123000 [2]辽宁工程技术大学矿业学院,辽宁阜新123000

出　　处：《应用基础与工程科学学报》2021年第2期387-398,共12页Journal of Basic Science and Engineering

基　　金：国家重点研发计划项目(2016YFC0600704);国家自然科学基金项目(51774165,51404130);辽宁省自然科学基金项目(20180550708)。

摘　　要：为研究低渗透硬岩渗透特性,以片麻岩为研究对象,采用多场耦合实验装置,开展不同围压、孔隙压力作用下岩石三轴压缩试验,分析了岩石渐进破裂过程中渗透率随围压、孔隙压力的变化规律,以及岩石渐进破裂过程不同阶段围压和孔隙压力对于片麻岩渗透率的影响程度.结果表明:岩石渐进破坏过程中,渗透率呈先减小后增加的变化趋势,在峰值强度附近渗透率出现突增;在轴压和孔隙压力一定时,随着围压增加渗透率逐渐减小,在裂纹非稳定扩展阶段和峰后残余阶段随着围压增加渗透率减小最明显;在轴压和围压一定时,随着孔隙压力增加渗透率略有增加,在裂纹非稳定扩展阶段随着孔隙压力增加渗透率增加最明显;高围压下试件内部会产生压缩带,压缩带会减弱孔隙压力对渗透率的影响;量化给出了渗透率随围压、孔隙压力变化的关系.In order to investigate the low permeability characteristics of hard rock,triaxial compression tests on gneiss were conducted at different confining pressures and pore pressures by using multi-field coupling experimental device.Then the analysis was about its permeability change as well as the influence of confining pressure and pore pressure on its permeability at different stages,during its progressive failure.The results demonstrate that during gneiss progressive failure,its permeability decreases firstly and then increases,and suddenly increases near the strength peak.When confining pressure and pore pressure are constant,its permeability decreases as confining pressure increases,and are most obvious in the stages of cracks unsteady growth and post-peak residual.When axial and confining pressures are constant,its permeability slightly increases as pore pressure increases,and are most obvious while cracks develop.The compression band will be produced inside samples under high confining pressure,which can weaken the effect of pore pressure on its permeability.The relations of gneiss permeability are given quantitatively with confining pressure and pore pressure.

关 键 词：三轴压缩 片麻岩 渐进破坏 低渗透率 孔隙压力 应力-应变曲线 

分 类 号：TU45[建筑科学—岩土工程]