邻近层同采工作面动压巷道失稳机理及错距优化研究

针对邻近层同采工作面回采巷道受多次采动影响变形量大的问题,采用理论分析、数值模拟和现场实测的方法对邻近层同采工作面在走向和倾向上的不同错距进行了研究。结果表明:1)邻近层工作面同采过程中,上下两工作面间岩层受多重采动影响经历了连续—似连续—非连续—散体的过程;2)走向错距不同时,邻近层工作面支承压力峰值、围岩破坏范围和破坏程度由大到小依次为错距20 m、错距0 m、错距50 m、错距60 m;3)受多重采动影响,下工作面运输巷位移随工作面的临近呈现台阶式增加,经历了2次逐渐增加—明显增加—稳定的过程。采区设计应考虑邻近层工作面同采产生的多重采动影响,设计并优化得出合理的走向错距和倾向错距,改善工作面回采时采场围岩尤其是回采巷道围岩的力学状态。

Instability mechanism of dynamic pressure roadway and staggered distance optimization in nearby-layer simultaneous working faces

AbstractAiming at the large deformation problems of roadway in nearby-layer simultaneous working faces, the paper has studied different staggered distances along strike and tendency in nearby-layer sim-ultaneous working faces by means of theoretical analysis, numerical simulation and field measure-ment. The results have shown that:1) Owing to the impact of multiple mining during the progress of simultaneous mining, strata between the upper and lower working faces have experienced the continu-ous-quasi continuous-discontinuous-dispersion process. 2) Under the different strike staggered distances, the peak of abutment pressure, the scope and degree of failure rock have changed in descending order from staggered distance of 20 m, 0 m, 50 m to 60 m. 3) Affected by multiple mining, the displacement of haulage roadway in the lower face has shown stepped increase with the approach of working face, and twice experienced the process of gradually increasing-obviously increasing and being stable. Multi-ple mining effects which have been produced by simultaneous mining should be taken into considera-tion in the mining area design, and reasonable strike staggered distance and tendency staggered distance should be designed and optimized to improve the mechanics state of the stope rock, especially sur-rounding rock of roadway.