动力扰动下特厚泥质顶板巷道围岩破裂演化及其能量机制研究

The anchoring effect of roadways with extra-thick argillaceous roof often decays or even fails, leading to roof collapse. How to eliminate roof caving accidents and ensure roof stability is the key point to further develop coal roadway bolting support technology. The current research focuses mainly on the effects of static or quasi-static disturbances, while the mechanism of roof caving accidents under dynamic disturbances has not been explained clearly and the energy mechanism of roadway instability failure is rarely discussed. To this end, the physical model experimental system of deep soft rock roadway destruction which can simulate the secondary fracture in rock strata is used to study the roadway fracture evolution and rupture characteristics under dynamic disturbance. Meanwhile, the rock mechanics test is conducted after the argillaceous roof is broken under static load to reveal the real evolution characteristics of deformation failure and strength attenuation under different dynamic loads, and the intrinsic relationship between deformation, strength damage and energy dissipation of specimens is also analyzed. The constitutive model of roadway - supporting system considering dynamic disturbance and surrounding rock damage is also constructed. The micromechanical mechanism of the roof caving in the process of continued rupture of fractured rock mass is explained. The research results provide scientific basis for further safety control of this kind of roadway.

特厚泥质顶板巷道常常出现锚固性能衰减甚至失效，造成顶板事故频发，如何消除冒顶、确保巷道顶板安全是进一步发展煤巷锚杆支护的关键。目前的研究主要集中在静态或准静态方面，针对动力扰动诱发巷道失稳机理的研究不足，巷道失稳破坏的能量机制更鲜有研究。为此，本项目采用能够模拟岩层内部次生破裂面的深部软岩巷道破坏过程模型实验系统，研究动力扰动下巷道裂隙演化规律与破裂特征；同时，借助岩石力学实验，探索泥质顶板在静载荷作用下破裂以后，在不同动力扰动下的变形破坏及强度衰减的真实演化特征，分析试件变形破坏、强度损伤与能量耗散的内在关系；构建考虑动力扰动和围岩损伤的巷道-支护系统本构模型，揭示动力扰动下裂隙岩体在继续破裂过程中诱发巷道顶板事故的细观力学机理。研究结果为进一步实现特厚泥质顶板巷道的安全控制提供科学依据。

特厚泥质顶板巷道常常出现锚固性能衰减甚至失效，造成顶板事故频发，如何消除冒顶、确保巷道顶板安全是进一步发展煤巷锚杆支护的关键。本项目采用能够模拟岩层内部次生破裂面的深部软岩巷道破坏过程模型实验系统，研究动力扰动下巷道裂隙演化规律与破裂特征；同时，借助岩石力学实验，探索泥质顶板在静载荷作用下破裂以后的变形破坏及强度衰减的真实演化特征，分析了试件变形破坏、强度损伤、能量耗散的内在关系。基于分形维数方法研究了动力扰动下围岩裂隙演化规律。针对巷道围岩裂隙演化特征，提出了“二次强力锚注”支护方案，旨在实现对巷道浅层破碎岩体和深部裂隙煤岩体的注浆加固，还实现了全长锚固，提高了初期支护强度，在山脚树煤矿成功开展了现场试验。项目共发表论文13篇，其中SCI/EI检索9篇，授权发明专利7项，培养硕士生4人。项目负责人获得贵州省科技进步三等奖2项、绿色矿山科学技术奖一等奖1项，获得贵州省青年科技奖，并入选贵州省优秀青年科技人才计划。