深孔预裂爆破在工作面强制放顶中的应用研究

Application of Deep-hole Pre-splitting Blasting Technology in Forced Caving of Working Face

15103工作面老顶为细粒砂岩,坚硬不易垮落,采取深孔爆破进行强制放顶。对深孔爆破参数进行设计,并采用PVC管作为载体,避免装药时炸药发生破坏,通过对爆破产生的CO含量及爆破后的通风时间的计算结果:CO理论计算值和检测值相符,爆破后通风时间不得低于520s。爆破效果表明:冒落岩块基本充满采空区,工作面老顶初次来压强度降低。

The old roof of 15103 working face is fine-grained sandstone, which is hard and not easy to collapse. Deep hole blasting is adopted for forced caving. The parameters of deep hole blasting are designed, and PVC pipe is used as the carrier to avoid the damage of explosive during charging. Through the calculation of CO content produced by blasting and ventilation time after blasting, the theoretical calculation value of CO is consistent with the test value, and the ventilation time after blasting shall not be less than 520 s. The blasting results show that the caving rock block is basically full of the goaf, and the initial compressive strength of the working face’s old roof is reduced.