煤矿软岩扩孔钻头研发及其锚固效果试验研究

Research and development on reamer bit of mine soft rock and experimental research on anchoring performance of reamed borehole

针对煤矿松软破碎软岩巷道采用锚杆支护时锚固力普遍偏低、达不到设计要求的问题,开发了煤矿软岩钻孔顶部扩孔钻头,并分别在实验室和煤矿井下现场进行了扩孔效果和扩孔锚固性能对比试验。试验结果表明:新研制的扩孔钻头在扩孔段扩孔直径比普通钻孔直径大5.3 mm左右,煤矿井下100 mm短锚固拉拔对比试验时,扩孔钻孔锚杆最大锚固力达112.3 k N,为普通钻孔锚固力的1.55倍。并且在树脂锚固剂和钻孔煤岩壁之间发生脱锚后,良好的机械摩擦阻力使锚杆锚固力一直保持基本不变,充分反映了软岩扩孔锚固的良好效果。

According to the general low bolt anchoring force and not meet the designed requirement of the bolt anchoring force when the bolt support applied to the mine soft and broken soft rock roadway,a top reaming head of the mine soft rock borehole was developed. The borehole reaming effect and the anchoring performance comparison test of the reamed boreholes were conducted in the lab and the underground mine site. The test results showed that a reaming diameter of a new researched and developed reaming head at the borehole reaming section could be about 5. 3 mm larger than the conventional borehole diameter. In the 100 mm short anchoring pulling comparison tests of the underground mine,the max anchoring force of the bolt in the reamed borehole could be up to 112. 3 k N and could be 1. 55 times higher than the anchoring force of the conventional borehole. Meanwhile,when the bonding failure occurred between the resin anchoring cartridge and borehole coal and rock wall,a good mechanical frictional resistance could keep a basic unchanging of the bolt anchoring force and could fully reflect excellent effect of the reamed borehole anchoring in soft rock.