山西煤矿采空区积水水害孕育机理与防治基础研究

In recent years, especially after the integration of resources，the water-inrush in goaf of Shanxi coal mine occurred frequently. The reason is that the mechanism of water-inrush is not completely clear, and the controlling foundation is not perfect. It is of great significance to study on the genesis mechanism and the prevention and control of water-inrush in goaf for the safe and efficient recovery of Shanxi Coal. The water-inrush accident in goaf is closely related to the amount of water, water quality, the development of fissures and the disturbance of the tunnel. Based on the water volume and water quality difference between the old empty areas, This project is mainly focused on the interaction of water and rock, to obtain the evolution mechanism of the stress and fracture field of the surrounding rock and the water chemical seepage-diffusion field in the goaf, under the excavation disturbance, the disaster model based on the water-rock interaction mechanism will be established to reveal the influence mechanism of water quality on space-time evolution of water-inrush quantity and the development of the crack, the water-inrush forecasting model will be established. Detection method of water in goaf with high precision is proposed ,and the technology research foundation with advanced grouting opportunity, position and scope will be studied, and the relief scope and relief mode after the water-inrush will be studied. All of these researches are to provide theoretical guidance and technical support for prevention and control of mining area water-inrush.

近年来山西采空区积水水害频发，尤其是后资源整合时代有愈演愈烈之势，究其原因是采空区积水水害的孕育机理不完全清楚，防治基础不完善。深入研究采空区积水水害孕育机理及防治基础对山西安全高效高回收率开采具有重要意义。采空区积水水害事故与采空区积水量、水质、裂隙发育状况、掘进扰动情况等密切相关。本项目基于积水老空区水质、水量的差异性，拟重点从水-岩交互作用角度，开展巷道掘进动态扰动作用下，积水采空区围岩应力场-裂隙场-水化学渗流-扩散场的时空演化机制的研究，建立积水采空区水岩交互作用致灾模型，揭示积水量、突水水质等对裂隙发育时空演化及突水量的影响机制，建立采空区积水水害预测模型，提出积水采空区高精度探测方法，研究含注浆时机、位置及范围等在内的超前注浆技术基础和含救灾范围及救灾模式等在内的水害救灾技术基础，为采空区积水水害的防治提供理论指导和技术支持。

针对山西省采空区水害突水机理复杂、探测精度较低、防治基础薄弱等难题，本项目围绕山西省矿井水害孕灾环境、采空区围岩破坏时空演化规律、采空区积水水害预测、采空区积水高精度探测及采空区积水水害防治技术基础，采用理论分析、数值计算、物理模拟、现场试验等方法对山西煤矿采空区积水水害孕育机理与防治技术基础中的关键科学问题开展了深入研究。.通过对山西省采空区水害案例广泛调研分析，总结了掘进过程中四种采空区水害模式：正位顶板型、侧位顶板型、侧帮周边型和迎头周边型；结合现场采空区水化学特征及煤岩吸水特性，分析了采空区动态积水过程，建立了动态积水量计算模型，结合流固耦合物理模拟刻画了采空区充水动态演化规律；分析了四种模式下巷道掘进过程中水的动态运移过程，提出了突水量的预测方法。.开展了掘进扰动影响下含裂隙煤岩的三轴加卸载试验，探究了水对含裂隙煤岩的损伤破坏影响规律，揭示了叠加载荷作用影响下煤岩裂隙的扩展机制。在此基础上，分析了采空区渗流场和围岩有效应力场，阐明了采空区水害孕育机理。.深入分析不同含水条件下煤矿采空区的瞬变电磁响应特征，建立了含不同电导率积水的单层及双层采空区模型，提出基于变分模态分解（VMD）的采空区瞬变电磁信号高精度解译技术，并在现场进行应用，提高了积水采空区的探测精度。 .测定了裂隙岩体注浆前后的力学特性，揭示了渗水环境中掘进应力对含裂隙注浆岩石的扰动机制。获得了疏水降压过程中水压及注浆条件对巷道围岩稳定性的影响规律，结合物理相似模拟与数值模拟分析了防水煤岩柱稳定性及隔水性，确定了防水煤岩柱最佳尺寸留设方法，为确定突水巷道被淹范围及最优避灾路线，构建了被淹巷道可视化计算模型，进行了水灾时避灾通路的可靠度计算。.项目成果不仅完善了采空区积水水害防治的技术理论体系，且在工程实际中进行了成功应用，为煤矿动力灾害防治、矿产资源开发、矿山环境保护等多学科提供了重要的理论指导及技术支持。