基于物理模拟与红外探测的冲击地压机理研究

Coal bumps at the working face occurred during coal exploitation at great depth has been a hot-spot problem world wide in the field of rock mechanics and mining sciences. The unstable slip between rock strata has been recognized as the major cause for occurrence of the coal bumps. Therefore, detection of the frictional slip between rock structures is of significance. The proposed project investigate the coal bump found in deep coal mining by means of construction of the large-scale geological model of the deep-coal-mining face using similarity materials for exploring the dynamical process of the bump induced by mining disturbances, and utilization of such measurement approaches as high-precision infrared thermography, speckle displacement monitoring and stress-strain gauges for obtaining the infrared temperature field, displacement field and stress-strain field, for quantitative analysis of the law of the release energy in coal bumps and establishment of the constitutive energy equation of the frictional slip of the rock masses. At the same time, a three-dimensional visualized numerical model will be constructed for the numerical analysis of the coal bumps occurred in deep coal mining. The numerical results will be compared to that obtained in the large-scale physical modeling tests for revealing the condition for initiating a coal bump. Novelty of this project lies in the application of the infrared thermography to the detection of the frictional slip condition of the large-scale model rock structures and quantitative analysis of the energy-release process. Outcome of this project will contribute to deepening our understanding of the coal bump mechanisms and providing support in the theoretical and technical aspects to forecasting the coal bumps in the deep coal mining.

深部煤炭开采工作面冲击地压是采矿和岩石力学领域的世界性难题，而岩层的不稳定滑动是造成冲击地压的主要原因。因此，开展岩体结构的摩擦滑动探测具有重要意义。本项目以深部条件下煤矿冲击地压为研究对象，利用相似材料构造出深部煤炭开采工作面的大尺度地质力学模型，研究其在地应力及开挖扰动作用下的冲击地压动态过程；采用高精度红外热像仪、散斑位移、应力/应变、声发射等测量方法，利用得到的红外温度场、位移场、应力应变场对冲击地压过程中的能量释放进行定量分析，建立岩体摩擦滑动的能量本构方程。同时构建深部煤炭开采工作面的三维可视化数值模型来模拟冲击地压，与物理模拟实验结果进行对比分析，揭示冲击地压的致灾机理和触发规律。研究的创新性在于用红外热成像技术识别大尺度岩体结构的摩擦滑动、并对该过程的能量释放进行定量分析，对煤矿冲击地压等动力学现象的机理认识和灾害预警提供理论与技术上的支持。

煤炭开采工作面巷道形状和尺寸效应是巷道失稳研究中一种常见的现象，但其演变规律和控制机理还不甚明了。科学试验是探索巷道失稳规律最主要的手段，然而试验研究中存在模型制作困难、影响因素考虑单一的问题。本项目针对上述问题，建立系列尺寸巷道模型进行红外探测及散斑测试实验，得出巷道形状和尺寸对巷道变形破坏影响的相关规律。随后利用自主研发采购的地声过程模拟试验系统开展煤岩真三轴加、卸载试验，获得煤岩在加卸、载过程中的损伤演化规律。针对煤岩实验中影响因素考虑单一的问题，对煤岩在不同预制裂隙、浸水时间、加载速率条件下进行单轴压缩试验来分析煤岩试件破坏形态、破坏前后其表面红外辐射温度场分布特征，从宏观破坏角度总结劣化性对煤岩失稳破坏的影响。本研究系统地对巷道失稳及煤岩劣化影响因素进行探索，旨在为煤炭安全开采和工程实践提供客观、可靠的依据。