针对建下条采煤柱回收和井下矸石处理的重大技术难题,提出矸石置换开采。通过阐述矸石充填巷集中与分散布置对地表移动的影响、分析置换开采留设煤柱的合理宽度,最终确定在条采煤柱中央集中布置2条矸石充填巷,充填巷尺寸为4.0 m×5.0 m(宽×高)、巷间煤柱宽4.0 m;基于数值模拟方法分析置换开采留设煤柱的稳定性、条采与置换开采老顶层面上垂直应力分布,得出置换开采留设煤柱满足煤柱强度设计要求、基本顶岩层结构保持稳定的结论。并运用相关的力学理论,分析置换开采后顶板的运动和变形特征,得出基本顶不会破断,地表变形没有超过建筑物允许变形范围。设计矸石置换开采充填工艺,该研究成果已成功应用于工程实践。
In order to solve the technical problems of mining strip extraction coal-pillar and waste disposal,the waste substitution extraction is proposed.By expounding the effect on surface movement while the layout of waste filling roadway is centralized and decentralized with analyzing feasible coal-pillar width of substitution extraction;the layout with two waste filling roadway placed in middle of strip extraction coal-pillar is determined and its width and height are 4.0 m×5.0 m,respectively;and the coal-pillar width between filling roadway is 4.0 m.Based on numerical simulation to analyze the stability of substitution extraction coal-pillar and vertical stress distribution of main roof in strip and substitution extraction,the conclusions with the strength of substitution extraction coal-pillar achieving design requirement and the strata structure of main roof remaining stable are achieved.By using the mechanics theory to analyze the character of roof moving and deformation after coal mining,the conclusion is gotten that the basic roof will not fail.The surface deformation operates within the allowable deformation of building.The research results have been successfully applied to coal mining.