坚硬顶板切顶巷道变形特征及其控制方法研究

Study on Deformation Characteristics and Control Method of Hard Roof Cutting Roadway

文章以山西某矿3104工作面切顶巷道为工程背景,采用理论分析、数值计算与现场监测相结合的方法对切顶巷道变形特征及控制方法进行了研究。结果表明:巷道实施切顶技术后,可以切断采空区顶板对巷道煤帮的应力传导路径,提高煤帮侧煤体的弹性模量及应力承载能力,降低煤体内部应力集中程度,增大巷道及工作面顶板卸压范围,有效限制巷道变形发展。据此提出了巷道顶板采用恒组大变形锚索、巷道煤帮侧采用无纵筋螺纹钢锚杆,以及巷道矸石侧采用“单体支柱+工字钢+金属网”加强支护的巷道变形控制方法。通过现场实践,切顶巷道顶板及两帮整体位移较小,保障了工作面切顶巷道的稳定性,可为坚硬顶板条件的矿山切顶巷道变形控制提供工程借鉴。

Taking the 3104 working face of a coal mine in Shanxi as an engineering background,the deformation characteristics and control methods of the roof-cutting roadway were studied by combining theoretical analysis,numerical calculation and field monitoring.The results show that after the roof cutting technology is implemented in the roadway,the stress conduction path of the goaf roof to the roadway coal can be cut off,the elastic modulus and stress bearing capacity of the coal body on the side of the coal gang can be improved,and the internal stress concentration of the coal body on the side of the coal gang can be reduced.Increase the pressure relief range of the roadway and the roof of the working face,and effectively limit the development of roadway deformation.Based on this,the study proposes that the roadway roof adopts the constant group large deformation anchor cable,the roadway coal side uses the non-longitudinal reinforced threaded steel bolt,and the roadway gangue side uses“single pillar+I-beam+metal mesh”to strengthen the support.Roadway deformation control method.Through field practice,the overall displacement of the roof and the two sides of the roof-cutting roadway is small,which ensures the stability of the roof-cutting roadway in the working face,and can provide engineering reference for the deformation control of the roof-cutting roadway in mines with hard roof conditions.