破碎围岩条件下开采扰动区LSMA的动力失稳

破碎围岩环境下大断面巷道开挖必然形成大尺度采空区(large scale of mined-out-area,LSMA),其围岩介质的变形与失稳行为及过程很复杂,主要涉及到开采扰动区(excavation dis-turbed zone,EDZ)范围内围岩力学性态及强度劣化特征、顶部岩层非稳态下沉与水平挤压变形耦合作用诱致动力失稳、深层围岩离层演化至局部化冒落失稳等,且其变形从微尺度演化为大尺度(寸)过程具有复杂的非线性特征,这为灾害治理带来挑战。基于现场调查,利用表面变形与深部离层规律综合监测与锚杆(索)力学性态试验及测试,结合室内物理相似模拟和数值模拟试验,深入分析复杂地质条件下松软破碎围岩局部化变形与演化失稳机理,为工程防灾和减灾提供科学依据。

Comprehensive analysis of dynamical destabilization for LSMA at excavation disturbed zone in the crushed rock conditions

The large scale of mined-out-area(LSMA) will be caused inevitably due to excavation of a large scale across-section in crushed rock-mass conditions,and its failure behavior and process is complex.Those mainly related to the mechanical properties and its deterioration in EDZ,non-stable subsidence of roof rocks and horizontal squeezing and its coupling effect so as to destabilization,delamination upon deepening rocks at roof induced to the localized dynamic destabilization.All of processes that the micro-scale deformation shifts to large scale manifested non-linear essential.This brought challenge for hazard prevention.The field monitoring includes surface deformation,the deepening of delamination and its corresponding movement regularity,in-situ experiment and test of bolt-cable mechanical property and engineering quality,etc.based on field geologic investigation.In addition,the model physical and numerical computation as prediction had been adopted.All those were intended to seek the mechanism on localization deformation and destabilization in softening and crushed rock-mass conditions at large.