浅埋煤层大采高工作面矿压显现规律及支架工作阻力研究

Mining Pressure Law and Working Resistance of Support in Face with Large Mining Height in Shallow Seam

为了研究浅埋煤层大采高工作面矿压显现规律并确定其合理的支架工作阻力,选取神东大柳塔煤矿5-2煤503工作面作为研究对象,通过薄板理论以及现场实测矿压数据对浅埋煤层大采高工作面矿压显现的规律进行了研究,并结合2种不同的理论计算公式对支架支护阻力进行分析。结果表明:52503工作面初次来压步距为64.4 m,与基于薄板理论计算得到初次来压步距61.7 m基本一致;正常回采期间周期来压步距在7.65~29.75 m之间波动,平均为19.16 m,动载系数1.45~1.57,平均为1.50,矿压显现强烈;来压期间工作面沿倾向方向的支架阻力呈"凸"型分布,其中工作面下部支架阻力约为中部的69.8%,工作面上部支架阻力约为中部66.5%;基于2种支护强度理论计算得到的工作阻力分别为17871 kN和19890 kN,均小于额定工作阻力为21000 k N的ZY21000/36.5/70D型液压支架,能够满足工作面上方顶板压力的支护要求。

In order to study the law of ground pressure appearance in the face with large mining height in shallow coal seam and determine its reasonable working resistance of support,the 5-2 coal 503 working face of Daliuta Coal Mine in Shendong is selected as the research object.The law of ground pressure appearance in the face with large mining height in shallow coal seam is studied through the thin plate theory and the field measured ground pressure data,and the support resistance is calculated by combining two different theoretical calculation formulas force analysis.The results show that the initial step distance of 52503 working face is64.4 m,which is basically consistent with 61.7 m calculated based on thin plate theory;the periodic weighting step fluctuates between 7.65 m and 29.75 m during the normal mining period,with an average of 19.16 m,a dynamic load coefficient of 1.45-1.57,an average of 1.50,which shows a strong mine pressure;during the weighting period,the support resistance along the inclined direction of the working face presents a"convex"type among them,the lower support resistance of the working face is about 69.8%of the middle part,and the upper support resistance of the working face is about 66.5%of the middle part;the working resistance calculated based on the two support strength theories is 17871 kN and 19890 kN respectively,which is smaller than the ZY21000/36.5/70 D hydraulic support with the rated working resistance of 21000 kN,which can meet the support requirements of the roof pressure above the working face.