开采扰动区(EDZ)内层状围岩变尺度损伤及失稳预计实验及综合分析

Experiment and comprehensive analysis of fracture characteristics and instability predictions for laminated rock mass in EDZ

在地下开采中常遇到层裂影响围岩力学行为,考虑到安全支护载荷及衍生动力灾害的可能性及工程应用,基于现场工程调查和室内多尺度煤岩动力破坏规律实验观察,建立了物理相似模型,完成了基于声发射(AE)的采空区覆岩变尺度损伤与断裂的模拟实验,对开采扰动区工作面周期来压(4个阶段)、围岩破裂与损伤的声发射特征参数(总事件与能率以及隐含的临界敏感性)等多元信息进行了综合比较,获得了老顶来压强度及支护阻力的定量化指标,这为工程现场EDZ内顶板大范围破断、围岩稳定性、破碎岩体失稳垮落等监测与控制提供依据。

Rock mass mechanical behavior dominated by laminations is encountered in underground excavations. Safe considerations for the support-force and its derived dynamic hazard probability or engineering application, it is important for the inherent stability of regularity and precursors. Based on the engineering, field investigation and coherent multiple-scales experiment observations and their regularity analysis, the physical models had been constructed for coal/rock mass damage and fracture in terms of AE test. The four stages periodic pressure variation at working-face, stability of EDZ, rock mass damage and fracture AE characteristic parameters, total event, energy release and its critical sensitivity, etc. , had been compared and analyzed, and the quantitative index of rock mass behavior and key roof workforce had been obtained. This provides monitoring way and field safe considerations for large roof rock mass damage, destabilization and collapse for broken rocks and its stability evaluation in EDZ.