切顶卸压爆破技术在沿空留巷中的应用

Application of top-cutting pressure relief blasting technology in gob-side entry retaining

在传统的煤柱护巷开采模式下,容易造成巷道变形不稳,应力集中,工作面替代紧张,煤炭资源回收率低等问题。为保持巷道稳定,解决采掘替代紧张局面,促进煤矿增效。在陈四楼煤矿2601综采工作面进风顺槽采用切顶爆破卸压沿空留巷技术,利用联合支护技术,分析确定切缝参数、爆破工艺参数,并在生产中成功实践。对照经切顶卸压的进风顺槽和未处理的回风顺槽的围岩变形情况,分析得出,经过切顶卸压和预裂爆破处理后的进风顺槽与未处理的回风顺槽相比,在应力作用范围内的进风顺槽与围岩的变形量明显减弱,其中进风顺槽受应力与回风顺槽相比降低46.90%。顶底板和两帮移动量相比,降低了82.71%和74.11%。大量数据表明,切顶卸压预裂爆破技术在空留巷道作业能有效阻断应力传递,降低应力在围岩中的积聚,可对巷道的稳定性进行有效控制,有利于实现安全高效的煤矿生产。

Under the traditional mining mode of coal pillar protection roadway,it is easy to cause unstable roadway deformation,stress concentration,tight working face replacement and low coal recovery rate.In order to maintain the stability of the roadway,solve the tense situation of mining substitution,and promote the efficiency of coal mine,the technology of top cutting blasting pressure relieving goaf-along roadway are adopted in the air intake channel of 2601 fully mechanized mining face in Chensilou mine,and the combined support technology are used to analyze and determine the slit parameters and blasting process parameters with successfully application in the production.Comparing with the deformation of surrounding rock of the air intake channel and the untreated return air channel,it is concluded that the deformation of the air intake channel and surrounding rock in the stress range of the intake channel is significantly weakened after the top cutting pressure relief and pre-split blasting,and the stress of the intake channel is 46.90%lower than that of the untreated return channel.Compared with the flow of the roof and floor and the two-side return air roadway,the flow is reduced by 82.71%and 74.11%.A large number of data show that the top-cutting pressure relief presplit blasting technology can effectively block the stress transfer,reduce the stress accumulation in the surrounding rock,and effectively control the stability of the roadway.The stability of the roadway is effectively maintained,which is conducive to the realization of safe and efficient coal mine production.