基于可释放应变能的岩石扩容准则  

Rock dilation criteria development based on releasable strain energy

作　　者：郭建强[1] 黄武峰 刘新荣[2] 陈建行 蒋建国 GUO Jianqiang;HUANG Wufeng;LIU Xinrong;CHEN Jianhang;JIAN Jianguo(College of Civil Engineering,Guizhou University,Guiyang 550003,China;College of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]贵州大学土木工程学院,贵州贵阳550003 [2]重庆大学土木工程学院,重庆400045

出　　处：《煤炭学报》2019年第7期2094-2102,共9页Journal of China Coal Society

基　　金：国家自然科学基金创新群体基金资助项目(50921063);贵州省科学技术基金资助项目(黔科合J字[2015]2037号)

摘　　要：针对当前扩容准则计算精度不高,且难以反映震源释放应变能对岩体扩容影响的问题,基于能量转化是物质物理过程的本质属性,通过理论分析和试验研究,从弹性应变能的角度对已有扩容准则进行了研究,并据此建立了广义扩容准则。结果表明,已有扩容准则将泊松比等于0.5看作是任意应力状态下材料扩容的前提;已有线性扩容准则未考虑中间主应力对扩容影响,且扩容应力随围压线性增加。在对扩容准则分析的基础上,从能量角度提出弹性应变能达到某一临界值时材料开始扩容,并据此建立广义扩容准则;该准则突破了材料扩容时泊松比恒为0.5的传统假设,且能反映中间主应力、弹性模量、泊松比及未知可释放应变能(或震源释放应变能等)等对岩体扩容的影响;当泊松比等于0.5时,该准则蜕化为既有扩容准则;应力水平相同时,泊松比越小,广义扩容准则计算的扩容应力越小;随中间主应力增加,广义扩容准则计算的扩容应力可能会降低。广义扩容准则为地震预报提供了理论支撑,既可计算受震源释放应变能影响的岩体是否扩容,又可计算发生扩容的岩体吸收应变能大小。三轴拉伸与三轴压缩条件下岩石扩容应力的计算表明,广义扩容准则可描述岩石的扩容特性,并分析了产生上述结果的内在机理。广义扩容准则对岩石扩容、地震预报、深部矿产资源的开采及地下工程的稳定性均具有重要意义。In order to overcome the problems that the calculation accuracy of current dilation criterion is not high and it is difficult for rock dilation to describe exactly the effect on the strain energy of the quake,based on the fact that energy transformation is the essential attribute of material physical process,the existing dilation criterion is studied from the angle of elastic strain energy through theoretical analysis and experimental study,and a generalized dilation criteria are established accordingly.The results reveal that the Poisson’s ratio of 0.5 is regarded as the premise of material dilation of arbitrary stress state in the existing dilation criterion,and the influence of intermediate stress on dilation is not considered in the existing linear dilation criterion,and the stress of dilation increases linearly to confining pressure.Based on the analysis of the dilatancy criterion,a generalized dilatancy criterion is proposed to the energy point of view when the elastic strain energy reaches a critical value.The criterion breaks the rule that the traditional assumption that Poisson’s ratio is constant at 0.5,and can reflect the influence of intermediate stress,elastic modulus,Poisson’s ratio and unknown releasable strain energy (or source releasing strain energy) on rock mass dilation.When Poisson ’s ratio equals 0.5,the criterion degenerate into the existing dilatancy criterion;when the stress level is the same,the smaller the Poisson’s ratio,the smaller the dilatancy stress calculated by the generalized dilatancy criterion;with the increase of the intermediate principal stress,the dilatancy stress calculated by the generalized dilatancy criterion may decrease.The generalized dilatancy criterion provides a theoretical support for earthquake prediction.It can not only calculate the dilatancy of rock mass affected by the strain energy released by the source,but also calculate the absorption strain energy of rock mass.The calculation of rock dilatancy stressed under triaxial tension and triaxial comp

关 键 词：可释放应变能 能量守恒 扩容准则 泊松比 

分 类 号：TU443[建筑科学—岩土工程]