基于能量转化机制的岩石强度的演化机理研究  

Study on the Strength Evolution Mechanism Based on the Energy Conversion Principal

作　　者：郭建强[1] 王姣姣 张钦榕 刘继 GUO Jianqiang;WANG Jiaojiao;ZHANG Qinrong;LIU Ji(College of Civil Engineering,Guizhou University,Guiyang 550003,Guizhou,China)

机构地区：[1]贵州大学土木工程学院,贵州贵阳550003

出　　处：《力学季刊》2024年第1期155-166,共12页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(41372356);贵州省自然科学基金(黔科合基础-ZK[2023]一般068)。

摘　　要：针对岩石强度的演化机理是提高强度准则计算精度与适用性的前提,基于能量转化是物质物理过程的本质属性,弹性应变能是材料破坏的内在机理,通过试验与理论研究,探究了围压、中间主应力及泊松比对岩石强度演化规律的影响.结果表明:岩石破坏与应力状态及岩石变形特性有关,忽略泊松比的影响是中间主应力效应提出的理论依据,并指出围压效应与中间主应力效应忽略变形影响,既与试验结果不一致,又是据此建立的强度理论精度较差的内在原因.岩石强度的演化是围压、中间主应力及泊松比共同作用的结果,并据此研究了静水应力状态下材料破坏特性、围压区间性及三轴拉伸强度恒大于三轴压缩强度条件.理论及试验表明,体现了围压、中间主应力及泊松比影响的强度理论具有较高计算精度与适用性.研究成果对于精准地描述岩石破坏特性,建立普遍适用的强度理论具有重要意义.The evolution mechanism of rock strength is required for improving the accuracy and applicability of strength criteria calculation.Considering the fact that the energy conversion plays a dominant role in the physical process of material,and the effect of the elastic strain energy on the material failure,the influences of the confining pressure,the intermediate principal stress and Poisson's ratio on the strength evolution of rock material are studied.The results show that the rock failure is related to stress state and rock deformation characteristics.Noting that neglecting the influence of Poisson's ratio is the basis for the intermediate principal stress theorem,the confining pressure effect and the intermediate principal stress effect ignore the influence of deformation,which is inconsistent with the experimental results and is also the internal reason for the poor accuracy of the corresponding strength theory.The evolution of rock strength is the result of the combined actions of the confining pressure,the intermediate principal stress,and Poisson's ratio.Based on this,the material failure characteristics,the confining pressure interval,and the condition that the triaxial tensile strength is always larger than the triaxial compressive strength under the hydrostatic condition were studied.It is shown from the theoretical and experimental results that the strength theory,which reflects the effects of confining pressure,intermediate principal stress,and Poisson's ratio,has high computational accuracy and applicability.The results of this paper are of great significance for accurately describing the failure characteristics of rocks and establishing universally applicable strength theories.

关 键 词：弹性应变能 强度演化 中主应力效应 泊松比 应力状态 

分 类 号：O346.4[理学—固体力学]