CAJ | 학술논문

为探究适应脆性硬岩加载破坏的强度准则,以杏山铁矿混合花岗岩为对象,根据室内试验获得岩石物理力学参数及岩样切片扫描图,基于颗粒流理论和PFC程序建立混合花岗岩颗粒细观几何模型,采用Fish语言编制加载命令流并调整相应函数,对岩石单轴和三轴(s3=40 MPa)刚性加载试验进行模拟.通过岩石全应力–应变试验与模拟曲线、AE声发射与裂纹监测成果等综合比较研究,获得荷载作用下混合花岗岩细观力学特性及微宏观破裂演化规律.在此基础上,结合岩石单轴刚性加载试验曲线,裂纹数、摩擦力能量与轴向应变关系曲线,以及FLAC模拟,对脆性硬岩黏聚力弱化–摩擦力强化(CWFS)强度准则模型参数进行优化研究与验证.获得杏山铁矿混合花岗岩CWFS强度准则模型参数:初始黏聚力为23 MPa,残余黏聚力为4.3 MPa,初始摩擦角为0°,残余摩擦角为46.3°,临界塑性应变 pce, pfe分别为0.0015,0.0037.该研究成果对杏山铁矿露天转地下开采围岩体破坏机制和力学本构关系研究和工程稳定性分析等具有重要的意义.
위탐구괄응취성경암가재파배적강도준칙,이행산철광혼합화강암위대상,근거실내시험획득암석물리역학삼수급암양절편소묘도,기우과립류이론화PFC정서건립혼합화강암과립세관궤하모형,채용Fish어언편제가재명령류병조정상응함수,대암석단축화삼축(s3=40 MPa)강성가재시험진행모의.통과암석전응력–응변시험여모의곡선、AE성발사여렬문감측성과등종합비교연구,획득하재작용하혼합화강암세관역학특성급미굉관파렬연화규률.재차기출상,결합암석단축강성가재시험곡선,렬문수、마찰력능량여축향응변관계곡선,이급FLAC모의,대취성경암점취력약화–마찰력강화(CWFS)강도준칙모형삼수진행우화연구여험증.획득행산철광혼합화강암CWFS강도준칙모형삼수:초시점취력위23 MPa,잔여점취력위4.3 MPa,초시마찰각위0°,잔여마찰각위46.3°,림계소성응변 pce, pfe분별위0.0015,0.0037.해연구성과대행산철광로천전지하개채위암체파배궤제화역학본구관계연구화공정은정성분석등구유중요적의의.
It takes migmatitic granite of Xingshan iron mine as the object to study the failure criterion of brittle hard rock. According to the physical and mechanical parameters from laboratory experiments and grains section scanning,micro-geometric model of migmatitic granite grains were built based on particle flow theory and PFC programs,loading codes were developed and some functions were adjusted by Fish language to simulate uniaxial and triaxial( 3s = 40 MPa) compression experiments. Based on comprehensive comparison and analysis of the complete stress-strain curves,acoustic emission and“crack”monitoring results from laboratory and simulation, the micro-mechanical characteristics and the cracks revolution laws from microcosm to macrocosm of migmatitic granite were obtained. On this condition,cohesion weakening and friction strengthening(CWFS) failure criterion model parameters of brittle hard rock were optimized and verified through laboratory curves of unixial rigid loading,relation curves between cracks and friction energy with plastic strain,and FLAC simulation. The optimized CWFS model parameters of initial cohesion,residual cohesion,initial friction angle,residual friction angle and critical plastic strain pce , pfe of migmatitic granite are 23 MPa,4.3 MPa,0°,46.3°,0.001 5 and 0.003 7 respectively,which is of great significance in theory and practice on the study of fracture mechanism,mechanical constitutive relations and engineering stability of rock mass during open pit mining transferring to underground mining in Xingshan iron mine.