不同单节理产状岩石力学性质数值模拟与强度预测模型  

Numerical simulation and strength prediction model of mechanical properties of rock mass with different single joint occurrences

作　　者：许珂 刘学生[1,2] 谭云亮[1,2] 李学斌 高宇栋 宋虎 唐颖钰 XU Ke;LIU Xuesheng;TAN Yunliang;LI Xuebin;GAO Yudong;SONG Hu;TANG Yingyu(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;State Key Laboratory of Strata Intelligent Control and Green Mining Co-Founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]山东科技大学能源与矿业工程学院,山东青岛266590 [2]山东科技大学省部共建矿山岩层智能控制与绿色开采国家重点实验室培育基地,山东青岛266590

出　　处：《中国矿业》2024年第4期158-170,共13页China Mining Magazine

基　　金：国家自然科学基金项目资助(编号:52174122,52074168);山东省自然科学基金优青项目资助(编号:ZR2022YQ49);山东省泰山学者工程经费项目资助。

摘　　要：节理岩石力学性质对于各类岩体工程长期稳定具有重要意义,而岩石的力学性质受节理产状影响极大,甚至起决定作用。为研究节理产状对岩石强度和破坏模式的影响机制,基于节理产状参数准确预测岩石的单轴抗压强度,采用PFC软件建立了不同单节理产状的岩石数值模型,开展了一系列单轴压缩数值模拟试验,得到了节理尺寸和倾角对岩石力学特性的影响规律:随着节理尺寸增大,岩石破坏模式逐渐由沿一定角度的剪切破坏变为节理端部裂纹扩展破坏,单轴抗压强度逐渐减小;随节理倾角增大,当节理倾角小于内摩擦角时,岩石的单轴抗压强度逐渐减小,破坏模式主要是节理端部翼裂纹扩展破坏;当节理倾角超过内摩擦角继续增大时,岩石的单轴抗压强度则逐渐增大,破坏模式主要是沿一定角度穿切岩石或次生裂纹扩展的剪切破坏。在此基础上,结合损伤力学和断裂力学理论提出了单节理岩石单轴抗压强度预测模型,充分考虑了由单节理产状差异导致的不同破坏模式对岩石强度的影响,模型参数易于获取。经算例验证,模型具有较高精度,能够满足工程现场需求。The mechanical properties of jointed rock are of great significance to the long-term stability of various rock mass projects,and the mechanical properties of rock are greatly affected by the occurrence of joints,and even play a decisive role.In order to study the influence mechanism of joint occurrence on rock strength and failure mode,the uniaxial compressive strength of rock is accurately predicted based on joint occurrence parameters.PFC software is used to establish a numerical model of rock with different single joint occurrence,and a series of uniaxial compression numerical simulation tests are carried out.The influence of joint size and joint dip angle on the mechanical properties of rock is obtained:With the increase of joint size,the failure mode of rock gradually changes from shear failure along a certain angle to crack propagation failure at the joint end,and the uniaxial compressive strength gradually decreases.When the joint dip angle is less than the internal friction angle,the uniaxial compressive strength of the rock decreases gradually with the increase of joint dip angle,and the failure mode is mainly the crack propagation failure at the joint end.When the dip angle of the joint exceeds the internal friction angle,the uniaxial compressive strength of the rock gradually increases,and the failure mode is mainly the shear failure of cutting rock or secondary crack propagation along a certain angle.On this basis,a prediction model of uniaxial compressive strength of single jointed rock is proposed based on the theory of damage mechanics and fracture mechanics.The influence of different failure modes caused by the difference of single joint occurrence on the strength of rock is fully considered,and the model parameters are easy to obtain.The example shows that the model has high precision and can meet the requirements of engineering site.

关 键 词：节理岩石 节理产状 破坏模式 强度预测模型 内摩擦角 

分 类 号：TD313[矿业工程—矿井建设]