强动载荷作用下高应力巷道围岩损伤效应与层裂结构失稳机理研究

The increase of mining depth causes the stress of the mining roadway to be close to or even surpass the limit of rock mass strength, susceptible to the interference of exterior load and likely to give rise to impact instability. This project aims at the damaging effect on the high-stress roadway surrounding rocks, and the failure process of the destabilizing layer-crack structures which are induced by a strong dynamic load. The project bases itself on meso-damage mechanics, and with the help of the localizing theory, explores the nonlinear evolution characteristics in the weakening process of the damage to roadway surrounding rocks, and the mechanisms governing the outbreak, expansion, and union of micro-cracks. It is intended to disclose the growth and development of surrounding rock cracks and the formative mechanism of macro-crack structures. Objectives also included are: investigating the weak surface wave effect and the free surface effect during stress wave under strong dynamic loading spreading in the surrounding rocks of roadways; establishing related quantification model which relies on basic numerical theories of multi-scale meshless method; clarifying the evolution mechanism of the macroscopic deformation caused by meso-damage in wall rock; grasping the law of physical field and proposing a criterion for judging macroscopic layer-crack structure instability, so as to offer the theoretical proof for the roadway surrounding rock stability analysis and supporting design.

随着采深增加，煤矿巷道应力状态接近或超过了岩体强度极限，极易受外载扰动产生冲击失稳。课题以强动荷载诱发的高应力巷道围岩损伤效应及层裂结构失稳灾变过程为研究对象，以细观损伤力学为基础，借助局部化理论，探索巷道围岩损伤弱化过程的非线性演化特性及微细观裂纹发生、扩展及联合机制，揭示围岩体裂隙发育、扩展及宏观层裂结构形成机理；探索强动荷载应力波在巷道围岩传播中的弱面波动效应、自由面效应；建立相关量化模型，基于多尺度无网格法数值理论，阐明围岩内部细观损伤对宏观变形的贡献及演化机理，掌握物理场规律，提出围岩宏观层裂结构的失稳判据，为巷道稳定性分析及支护设计提供理论支持。

随着采深增加，煤矿巷道应力状态接近或超过了岩体强度极限，极易受外载扰动产生冲击失稳。.本项目通过四年的研究，已经圆满完成了申请计划书所规定的研究内容，在强动荷载应力波-高应力围岩-局部化裂隙体系、高应力巷道围岩开挖及强动载荷下的变形局部化-裂隙发育-层裂板、围岩变形局部化特点和层裂板动力失稳无单元法等方面取得了一些新的试验与理论研究成果。.项目在理论上揭示了强应力波穿越裂隙面的波场分解过程振幅衰减、振动强度降低、持续时间增加的规律，揭示强应力波传播自由面效应；提出了巷道围岩在强动荷载环境下细观局部化变形及裂纹的成核、扩展和汇合模型和本构模型；建立了高应力巷道围岩开挖及强动载荷下的变形局部化-裂隙发育-层裂板形成的渐进力学模型，初步建立了强动荷载下围岩局部化RKPM无网格法数值分析方法。.项目按计划正常进行，完成了预期目标。在本项目的资助下，已在国内外核心期刊和重要学术会议上发表署名国家自然科学基金项目资助的研究论文90篇（SCI、EI收录33篇），会议论文7篇，出版著作1部，获得申请授权国家发明专利16项，获得省部级科技进步奖4项。研究内容和项目组成员均未进行大调整。