层理发育软硬层叠岩体大密集系数爆破技术研究

Study on big dense coefficient blasting technology of soft and hard stratigraphic overlay and stratified development rock mass

为了解决露天台阶传统爆破方法难以克服的诸多困难,依据黑岱沟露天煤矿岩体层理发育、软硬岩层叠置的实际条件,提出了利用空气间隔装药技术均衡炮孔内爆轰压力、毫秒延时逐孔起爆和大密集系数爆破技术方案。用三维数值模拟了双排多炮孔在爆炸荷载作用下逐孔起爆时,台阶爆破困难部位的岩体受力状态,证实了方案的可行性,并用现场试验验证了数值模拟确定的主要爆破技术参数的可用性。空气间隔装药、毫秒延时逐孔起爆和大密集系数布孔等技术的综合利用,实现了层理发育、软硬岩层叠置复杂岩性条件下,露天台阶深孔爆破爆堆松散、无根(拉)底和岩石破碎块度均匀、大块率低的良好效果,经济效益显著。

In order to solve many difficulties which are difficult to overcome by traditional blasting method of open-pit bench, according to the actual conditions of rock strata development and hard and soft rock layers stacked in Heidaigou open-pit coal mine, it is proposes that a method of using air decked charge to equalize the detonation pressure in blast hole and the big-dense coefficient blasting technical program and hole by hole detonation. The three-dimensional numerical simulation is used to study the mechanical properties of blasting rock mass on double-row and multi-hole blasting, the feasibility of the scheme is confirmed, and the field test verifies the feasibility of the main blasting technical parameters determined by numerical simulation. Production applications show that the rational use of air decked charge, microsecond interval delay's hole by hole detonation and big dense coefficient holes layout can achieve a significant economic benefits and the good results of blasting burst loose, no bulk , no the hard bottom and low block rate in complex rock of stratification development and soft and hard rock layers stacked.