不同老顶条件下直接顶硬度对工作面超前支承压力的影响

Influence of Immediate Roof Hardness on Lead Abutment Pressure at Face with Different Conditions of Main Roof

超前支承压力的分布规律对煤矿开采过程中冲击地压、煤与瓦斯突出等灾害有很大影响。应用UDEC2D4.0离散元数值模拟软件,研究了不同顶板条件下采煤工作面超前支承压力的分布规律。随着直接顶硬度的增大,支承压力的应力集中系数和影响范围不断增大,且支承压力峰值逐渐向采煤工作面方向靠近。老顶坚硬工作面支承压力的应力集中系数、峰值与工作面煤壁的距离以及影响范围均大于老顶软弱的工作面。研究成果可为煤矿生产中采煤工作面支护参数的选取提供参考。

Distribution of the lead abutment pressure has direct influence on disasters in mining,such as rock burst,coal and gas outburst.By using discrete element simulation software UDEC2D4.0,the distribution of the lead abutment pressure at face with different conditions of main roof was researched.With the increasing of the immediate roof hardness,the stress concentration coefficient and range of influence of the lead abutment pressure was increased,and the position of peak pressure was closed to face.In addition,the stress concentration factor,distance of peak pressure and face and range of influence of the lead abutment pressure at face with the hard main roof is larger than others with the weak main roof.The research results can provide reference for rational selection of face support parameters in field production.