基于承压水单孔放水实验的底板水害精准注浆防治

Floor precise grouting for prevention and control of water based on confined water single-hole drainage experiment

我国华北型煤田普遍受底板承压水威胁,底板注浆改造是承压水害防治的有效途径。但注浆改造层位多为非均质的灰岩,其注浆地质条件复杂多变,使得注浆工程效率有限。为了提高底板注浆水害防治的效率,开展基于承压水单孔放水实验的底板精准注浆研究。以渭北煤田,特别是澄合矿区董家河煤矿为研究背景。在分析研究区底板水害防治特征的基础上,结合底板精准注浆内涵,针对性研发了单孔放水实验装置及配套使用技术。在开展单孔放水实验的基础上,结合突水优势面理论提出了底板分类注浆技术。研究结果表明:通过设置定流量控制阀,可以实现单孔放水实验,获取承压水的渗透系数 K 和富水系数 q 等参数。结合环向非完整井的设计,可以获取承压水水平方向上主要的径流方向。依据单孔放水实验获取的水文参数,结合突水优势面理论,注浆条件类型可以划分为5大类7小类,包括不富水型、 Q - S 曲线直线Ⅰ型、 Q - S 曲线直线Ⅱ型、 Q - S 曲线抛物线Ⅰ型、 Q - S 曲线抛物线Ⅱ型、 Q - S 曲线幂函数型、 Q - S 曲线对数型。依据钻孔注浆条件的重要性,给出了每种类型钻孔的注浆工艺。通过工程实践应用,采用分类注浆技术的注浆工程提高了注浆效率,有效控制了底板水害。研究成果为华北型煤田底板承压水害信息化防治提供了新的技术和设备。

The North China type coalfields are generally threatened by the floor confined water,and the grouting transformation of floor is an effective way to prevent and control the confined water disaster.However,most of the grouting transformation layers are heterogeneous limestone,and the grouting conditions are difficult to ascertain,so the efficiency of grouting is limited.In order to improve the effect of prevention and control of floor water hazards,the floor precise grouting based on confined water single-hole drainage experiment had been studied.The Weibei Coalfield,especially Dongjiahe Coal Mine in Chenghe Mining Area was taken as the research background.Based on the analysis of the characteristics of floor water hazard prevention and control in the study area,and combined with the connotation of floor precise grouting,a single-hole drainage experimental device and its supporting application technology had been developed.On the basis of single hole drainage experiment,combined with dominant surface water inrush theory,the floor classification grouting technology had been proposed.The results show that the single-hole discharge experiment can be realized by setting a constant flow control valve,and the permeability coefficient K and water enrichment coefficient q of confined water can be obtained.Combined with the design of circumferential incomplete wells,the main runoff direction in the horizontal direction of confined water can be obtained.According to the hydrological parameters obtained from the single-hole discharge experiment and based on the dominant surface theory of water inrush,grouting conditions can be divided into five categories and seven sub-categories,including non-water-rich type, Q-S curve straight line type I, Q-S curve straight line type II, Q-S curve parabola type I, Q-S curve parabola type II, Q-S curve power function type,and Q-S curve logarithmic type.According to the importance of different grouting conditions,each type of grouting technology was proposed.The application in engineering practice shows that the grouting project using classified grouting technology improves the efficiency and effectively controls the floor water hazard.The research results provide new technology and equipment for the prevention and control of confined water hazards in the floor of North China Coalfield.