含水率对钻孔裂隙发育的影响

Study on the Law of Drilling Fracture Development of Different Water Content Briquettes

钻孔周边存在裂隙产生于发育,造成钻孔孔壁出现漏风通道,造成瓦斯抽采的低效率,因此裂隙发育的情况成为研究重点。本文基于对不同含水率的型煤进行钻孔作业,并在钻孔前、钻孔后以及注浆后进行型煤内部的声速测试,研究不同含水率型煤的裂隙发育规律。结果表明:通过钻孔前后的声速分析,6%含水率的在钻孔前后的声速变化较小,而12%含水率的声速变化较大。

Because of cracks exist on the periphery of boreholes,resulting in the leakage of the borehole wall and the low efficiency of gas extraction,so the development of fissures has become the focus of research.Based on the drilling operation of mould coal with different moisture content,this paper tests the sound speed inside the briquette before drilling,after drilling and after grouting,so as to study the fracture development law of briquette with different moisture content.The results show that:through the analysis of the sound velocity before and after drilling,velocity change of 6%moisture content before and after drilling is smaller,and the variation of sound velocity of 12%moisture content is larger.