摘要
为探究中砂岩破坏全过程中的渗透特性及损伤演化特征,对中砂岩进行了三轴渗透及声发射试验。研究结果表明:渗透率随着应力加载全过程呈先减小后增大的整体趋势,在峰值应力前后达到最大值;围压越大,渗透率越小;体积变形扩容点与渗透率的突变点相对应,更能准确反映渗透性的变化;渗透测试过程中的声发射现象是一个呈阶段性的演变过程并与渗透率大小的变化趋势相对应;围压越大,声发射现象越滞后;利用声发射参数,基于Weibull分布函数计算得到的损伤表明,应力对砂岩的损伤主要发生在应力加载阶段,渗透损伤相对较小且主要集中于屈服阶段之后;围压越大,渗透损伤量所占比重越小。
In order to explore the permeability characteristics and damage evolution characteristics of medium sandstone in the whole damage process, the penetration and acoustic emission test were performed under triaxial conditions. The study shows that permeability has a similar evolution characteristics and first decreases and then increases under different confining pressure, the permeability decreases gradually with the increase of confining pressure;The volume deformation expansion point corresponds to the abrupt change point of permeability, which can more accurately reflect the change of permeability; The evolution process of acoustic emission reflects the change trend of permeability and is phase change, the greater the confining pressure is, the more the acoustic emission phenomenon is ; Based on the Weibull function distribution calculation of the damage by acoustic emission parameters shows that stress loading stage is the main factor of sandstone damage, and the infiltration damage is relatively small and mainly concentrated in the yield stage, the greater the confining pressure is, the smaller the proportion of seepage damage is.
作者
李傲
LI Ao(Chongqing Water Resources and Electric Engineering College, Chongqing 402160,China)
出处
《四川建筑科学研究》
北大核心
2017年第1期70-75,共6页
Sichuan Building Science
关键词
中砂岩
渗透率
声发射
Weibull函数
损伤
medium sandstone
permeability
acoustic emission
Weibufl function
damage
