煤矿掘采空间垮塌岩体稳定性与救援通道构建

Stability of collapsed rock body in coal mine excavation space and construction of rescue channel

煤矿地质动力灾害发生后,往往会造成掘采空间巷道发生垮塌堵塞,严重威胁煤矿井下工作人员安全。垮塌形成的松散破碎堆积体力学结构、堆积形态十分复杂,如何快速清理垮塌堆积体并构建救援通道是亟待解决的科学问题。在分析灾变垮塌体结构运移规律及救援通道构建研究现状和问题的基础上,针对垮塌堆积体堆堵机理复杂、扰动变形规律不明的特点,首先基于颗粒流数值模拟软件构建了垮塌堆积体二维计算模型,探究了在垮塌堆积体内部构建救援通道过程中颗粒的运动特征,明晰了其掘进扰动规律;其次分析了不同区域构建救援通道条件下堆积体内应力重分布特征,优选了救援通道在垮塌堆积体中的构建位置;最后根据垮塌堆积体的力学特征及堆积形态,提出了一种新型救援通道快速构建方法。结果表明:在构建救援通道掘进扰动的影响下,垮塌堆积体的岩体均有向开挖空间运动的趋势,距离开挖位置越远的区域受到扰动影响越小;垮塌堆积体向开挖空间的二次塌落主要以垂直方向为主,水平方向次之;左下方开挖稳定后,垮塌堆积体呈"梯形",中下方开挖稳定后,垮塌堆积体呈“V”形。综合考虑救援通道构建的二次扰动影响、支护结构稳定性与垮塌堆积体物源结构,救援通道构建位置选择在垮塌堆积体中部区域为宜。

Geodynamic disasters in coal mines often cause the collapse and blockage of the excavation space roadway,which seriously threatens the safety of underground workers in coal mines.The mechanical structure and accumulation form of the loose and broken accumulations formed by the collapse are very complicated,so how to quickly clear the collapsed accumulations and construct the rescue passage is an urgent scientific problem to be solved.On the basis of analysing the current situation and problems in research on the structural transport laws of catastrophic col-lapsed bodies and the construction of rescue routes,and in view of the complexity of the mechanism of pile blocking of collapsed piles and the uncertainty of the laws of disturbance and deformation.Firstly,a two-dimensional computa-tional model of the collapsed pile was constructed based on the particle flow numerical simulation software,and the motion characteristics of the particles in the process of constructing the rescue channel inside the collapsed pile were investigated,and the disturbance law of its excavation was clarified;Secondly,the stress redistribu-tion characteristics in the pile under the conditions of constructing the rescue channel in different areas were analysed,and the construction location of the rescue channel in the collapsed pile was preferred;Finally,according to the me-chanical characteristics of the collapsed pile and the pile morphology,a new rapid construction method of the res-cue channel is proposed.The results show that:under the influence of the disturbance of excavation to build the res-cue channel,the rock body of the collapsed pile has a tendency to move towards the excavation space,and the farther away from the excavation position,the smaller the influence of the disturbance is;the secondary collapse of the col-lapsed pile to the excavation space is mainly in the vertical direction,and the horizontal direction is secondly;the col-lapsed pile is in the shape of a“trapezoid”after the excavation is stabilised in the lower left,and in the shape of“V”after the excavation is stabilised in the middle and lower parts of it;Considering the influence of secondary disturbance,the stability of the supporting structure and the source structure of the collapsed pile,it is appropriate to choose the location of the rescue channel in the middle of the collapsed pile.