摘要
为探讨裂隙面变形参数对非贯通裂隙岩体压缩特性的影响,基于ABAQUS中的应变软化模型描述岩石力学行为,采用扩展有限元法(XFEM)计算裂纹扩展路径,重点研究了裂隙几何参数(长度、倾角、中心距、排距、数量)、强度参数(裂隙面摩擦因数)、变形参数(裂隙面法向刚度及切向刚度)以及围压对裂纹扩展路径和岩石压缩力学特性的影响。研究结果表明,裂隙岩体单轴抗压强度和弹性模量随裂隙长度和数量的增加而不断降低;随着裂隙中心距和排距的增大,裂纹面间相互作用减小,裂隙岩体抗压强度和弹性模量均有不同程度的提高;随着围压、裂隙面摩擦因数、裂隙面法向刚度及切向刚度的增大,裂隙岩体抗压强度和弹性模量均随之提高;随着裂隙倾角由0°增加至75°,试样的抗压强度先减小后增大,并在倾角为45°时最小,呈开口向上的抛物线规律变化;裂隙长度、数量、倾角、中心距、排距以及围压对裂纹扩展路径影响较大。
In order to discuss the influence of the deformation parameters of the crack surface on the compression characteristics of the rock mass with non-persistent cracks,based on the strain softening model in ABAQUS to describe the mechanical behavior of the rock mass,the crack growth path was calculated by the extended finite element method(XFEM).And the emphasis was given to study the influences of the crack geometric parameters(length,inclination angle,center distance,row spacing,number),strength parameters(friction factor of the crack surface),deformation parameters(normal stiffness and tangential stiffness of crack surface),as well as confining pressure on crack growth path and compression mechanical behaviors of rock mass.The results are concluded as follows.Firstly,the uniaxial compressive strength and elastic modulus of cracked rock mass decrease with increasing crack length and number.Secondly,with the increase of crack center distance and row spacing,the interaction between crack surfaces decreases,thereby the compressive strength and elastic modulus of the samples increase.Thirdly,the compressive strength and elastic modulus of cracked rock mass increase with increasing confining pressure,crack friction coefficient,crack normal stiffness and crack tangential stiffness.Finally,with the crack inclination angle increasing from 0°to 75°,the uniaxial compressive strength of rock mass firstly decreases and then increases,and the minimum compressive strength can be obtained when the crack inclination angle is 45°,which shows a parabolic change law with hatch toward up.The crack length,number,inclination angle,center distance,row spacing and confining pressure have much influence on crack growth path.
作者
宋孝天
刘红岩
SONG Xiaotian;LIU Hong yan(College of Engineering&Technology,China University of Geosciences(Beijing),Beijing 100083,China;Key Laboratory of Deep Geodrilling Technology of Ministry of Natural Resources,Beijing 100083,China)
出处
《矿业研究与开发》
CAS
北大核心
2023年第1期76-85,共10页
Mining Research and Development
基金
北京市自然科学基金项目(8222031)。
关键词
裂隙岩体
压缩破坏
XFEM
裂隙面法向刚度
裂隙面切向刚度
Cracked rock material
Compression failure
XFEM
Crack normal stiffness
Crack tangential stiffness
