基于损伤演化的砂岩能量参数围压效应研究  

Confining pressure effect on energy parameters of sandstones based on damage evolution

作　　者：程虹铭 杨小彬[1] 刘隽嘉[1] 陈寻璐 Cheng Hongming;Yang Xiaobin;Liu Junjia;Chen Xunlu(School of Emergency Management and Safety Engineering,China University of Mining&Technology-Beijing,Beijing 100083,China;School of Coal Engineering,Shanxi Datong University,Datong Shanxi 037003,China)

机构地区：[1]中国矿业大学(北京)应急管理与安全工程学院,北京100083 [2]山西大同大学煤炭工程学院,山西大同037003

出　　处：《矿业科学学报》2020年第3期249-256,共8页Journal of Mining Science and Technology

基　　金：国家自然科学基金(50904071,51274207);大同市科技局项目(2019159)。

摘　　要：岩石材料损伤演化状态所对应的特征参数,对岩土工程的稳定性设计、预测及监测等至关重要。本文开展不同围压下砂岩分级循环加卸载试验,利用横向应变法和体积应变法确定受载岩样损伤演化状态,基于损伤演化状态分析各阶段、各损伤演化特征点处能量参数演化特征及与围压的关系。结果表明:不同围压下,峰前各阶段能量参数随应变增大而增大;随着围压的增大,峰值应力处的弹性应变能、耗散能突变向峰后转移;峰后残余应力阶段各能量参数降低并趋于平缓。σcc处能量参数与围压成幂函数下降关系,且耗散能随围压增大趋于稳定;σci、σcd及σp处能量参数随围压呈线性增加,各特征点处输入能量与弹性应变能差值随围压的变化趋势较小,且在σcd处两者相对差值最小,输入能量转化为弹性应变能最多。The characteristic parameters corresponding to damage evolution state of rock material are crucial to designing,predicting and monitoring the stability of geotechnical engineering.The cyclic loading-unloading triaxial compression tests of sandstones were implemented with different confining pressure,and the damage evolution state were determined by the lateral strain method and the volumetric strain method,and the energy parameters phased evolution,the energy evolution of characteristic points corresponding to damage evolution state and relation with confining pressure,were analyzed based on damage evolution state.The result showed that:with different confining pressure,the energy parameters increased with the increase of the strain at each stage before the pre-peak;the mutation of the elastic strain energy and the dissipation energy at peak stress transferred to post-peak with the increase of the confining pressure;the energy parameters decreased to level off at residual stress stage.The energy parameters had a power function decrease with confining pressure at the point of σcc,and the dissipation energy decreased to level off with the increase of the confining pressure.At the points of σci,σcd and σp,the energy parameters increased linearly with confining pressure,and there was small change trend of the difference between the total input energy and the elastic strain energy with the confining pressure at the different characteristic points,and the relative difference between the total input energy and the elastic strain energy was minimum,and the total input energy converted into the elastic strain energy was maximum at point σcd.

关 键 词：砂岩 损伤演化 特征点 能量参数 围压 

分 类 号：TU45[建筑科学—岩土工程]