自旋锚杆在煤巷支护中的应用
Application of Screw Bolts in Coal Roadway Support
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摘要: 为解决象山煤矿围岩破碎煤巷支护中树脂锚杆钻孔易塌孔、安装失效率高等难题,引进了自旋锚杆支护技术,分析了自旋锚杆的结构特点和作用机理。对拉拔力进行理论计算,由拉拔试验结果得知,不同长度的锚杆理论计算值与实测值平均误差在8%左右。在此基础上,针对北二采区5号煤运输下山采用自旋锚杆支护技术,并对其应用成果进行数值模拟分析和现场试验,结果表明:自旋锚杆安装成功率达95%;增阻快,当围岩变形为5 mm时,锚固力已增至33 kN左右,并随着围岩变形进一步增加;围岩变形量小于20 mm,证明自旋锚杆支护技术有效控制了该煤层巷道围岩变形。Abstract: In order to solve collapse and high installation failure rate problems of bolts holes drilling procedure during the period of broken surrounding rock support in Xiangshan Mine, screw bolts technology was introduced. Based on the analysis of structural characteristics and mechanism of the screw bolts, the pulling force has b een calculated theoretically. According to the trial results, theoretical values of anchors with different lengths had an average error ( 8%) compared to the practical one s. Moreover, the new screw bolts support technology was proposed and applied in the downdip hauling roadway of No.5 coal seam. The numerical simulation analysis r esults suggested that the rate of successful screw bolts installation was 95% and the resistance force increased fast. While the rock deformation was 5 mm, the anchori ng force had raised to about 33 kN. With further rock deformation, the rock displacement was less than 20 mm. These results indicated that screw bolt technology was effective to control the surrounding deformation of the coal roadway.