不同开采参数条件下保护层开采卸压效果研究

Study on Pressure Relief Effect of Protective Layer Mining Under Different Mining Parameters

为探究不同开采参数条件下的保护层卸压效果,系统性分析了开采高度、层间距、工作面长度对被保护煤层的垂直应力分布规律以及底板卸压程度的影响,通过计算卸压系数进行了量化表征。结果表明:开采高度的增加与层间距的降低将导致卸压效果的提升。保护层的卸压量随着工作面长度的增加而逐渐降低,卸压范围随工作面长度增加而增长。对底板的卸压程度进行分析,表明开采高度与工作面长度的增加有利于提升底板的卸压效果。层间距的影响则存在两级分化特征,当层间距小于20 m时,底板卸压的临界深逐渐增加,层间距大于20 m时,底板卸压的临界深度逐渐降低,并逐渐达到稳定。

Protective layer mining is an effective technical measure to prevent and control rock burst of coal seam groups.In order to explore the relief effect of protective layer under different mining parameters,the influences of mining height,layer spacing and working face length on vertical stress distribution and floor relief degree of protected coal seam were systematically analyzed,and quantified by calculating the relief coefficient.The results show that the increase of mining height and the decrease of layer spacing will lead to the improvement of pressure relief effect.The pressure relief of the protective layer decreases gradually with the increase of the length of the working face,and the pressure relief range increases with the increase of the length of the working face.The analysis of the pressure relief degree of the floor shows that the increase of mining height and working face length is conducive to improving the pressure relief effect of the floor.When the layer spacing is less than 20 m,the critical depth of floor pressure relief gradually increases,while when the layer spacing is greater than 20 m,the critical depth of floor pressure relief gradually decreases and gradually reaches stability.