小断面渗水岩石立井爆破的问题与对策

分析了在实际条件下小断面立井爆破所存在的问题,包括使用的炸药密度小、爆速低,不利于进行致密花岗岩爆破和水炮孔装药;作业面水的存在,影响布孔、钻孔、装药、堵塞、引爆等爆破施工环节。通过增加炮孔布置的数量、保证必要的爆破炸药单耗、采取一系列有效的施工技术和爆破技术等措施,减小或避免水的不利影响,改善了爆破效果。实践表明,空孔在作业面有水的致密花岗岩立井掏槽中仍能起到显著作用;立井渗水量大时可利用水覆盖控制爆破飞石,降低井口的防护要求。

PROBLEMS IN BLASTING SMALL SECTION VERTICAL WELL WITH WATER SEEPING AND ITS COUNTERMEASURES

In this paper the problems existing in excavating small section vertical well by blasting was discussed.These cover the problems such as the factors which could cause the difficulty of blasting design and operation,including low density and low detonation velocity of explosive which make unfavorable for the blasting fine granite and loading charge in the short hole full of water,and water on working face which influences the hole arrangement,drilling,explosive loading,hole stemming and igniting.The problems were solved by increasing the number of the hole to guarantee the essential explosive loading and by regulating the blasting parameters to minimize or avoid the negative influence of water.The practice showed that the obvious positive effect was obtained in excavating of fine granite vertical well with the empty holes full of water.The water cover could control the flyrocks and degrade the prevention for the fence at the mouth of the well.