粉煤灰高水短壁部分充填技术研究与实践

针对承压水上、建筑物下开采技术难题,在系统分析粉煤灰高水材料特性、充填工艺和禁止井工煤矿使用的设备及工艺目录(2008年第2批)"巷道式采煤"的基础上,通过理论分析、室内试验及现场实测等方法,对粉煤灰高水短壁部分充填工作面设计及围岩控制下效果进行了系统研究。主要结论包括:1对粉煤灰高水充填材料发泡机理、材料特性、充填工艺进行了分析;2提出了短壁部分充填工作面设计方法及采-充程序及工艺,数值模拟表明50 m充填联合支撑体与20 m采空区底板塑性区范围为6~8 m,顶板塑性区范围10~12 m;3充填体密实性、原位强度和安全系数表明,充填体与顶板接顶率大于95%,原位强度1.93 MPa,安全系数6.8,粉煤灰高水充填体联合支撑体系能够保持围岩稳定;4充填体和底板变形监测表明,短壁部分充填采场顶板最大下沉量80 mm,底板最大破坏深度8 m,底板隔水层厚度在安全范围之内。在埠村煤矿9111工作面进行了现场实施,相关研究成果可以对类似条件下的煤炭开采提供参考。

Research and practice on shortwall part filling technology using fly ash high-water material

In terms of the technical problems of mining above confined water and under building,on the basis of the systematic analysis on the properties of fly ash high-water material,filling process and “tunnel type coal mining” which is in the prohibited equipment and technology directory in underground coal mining,through theoretical analysis,indoor experiments and field experiment and so on,a fly ash high-water shortwall part filling panel design and related control technologies were studied systematically.The main study topics and conclusions are summarized as follows:① The foaming mechanism of fly ash high-water filling material,properties,filling processes were analyzed;② A shortwall part filling panel design method and mining-filling program and techniques were put forward.The numerical simulations demonstrated that the floor plastic zone was 6-8 m and the roof plastic zone was 10-12 m based on the joint support system of 50 m filling body and 20 m goaf;③ The filling body density,in situ strength and safety coefficient were showed that the top ratio of the filing body and roof was more than 95%,the in-situ strength was 1.93 MPa,the safety coefficient was 6.8,and the joint support system of fly ash high water filling body could be maintained stable;④ The filling body and floor deformation monitoring showed that the roof maximum subsidence was 80 mm,the floor maximum damage depth was 8 m,and the confining bed thickness of the floor was within the safety limit.The study was carried out at No.9111 coal face in Bucun Coal Mine.The relevant research findings could have some referential significance and application value in similar mining conditions.