在坑探工程中,現在已經广泛的推行了直線龟裂掏槽。在岩石爆破性差、坑道断面小的条件下,与錐形掏槽比較起来,也已充分显示出它的优越性。但是,它的爆破率还常常不能令人滿意。特别是遇到靱性大的岩石时,“打筒”、“崩半节”、“挤死”、“戴眼镜”(有人称它們为直線龟裂掏槽四大症)的现象尚为严重。产生这种情况的原因。一般認为是由于空隙眼太小太少,炮眼间距不当所致。毋庸置疑,这是造成爆破效果不良的重要因素,但并非全部。有的工作面打了1～3个大直徑的空隙眼,也未能保証爆破效果良好。事实告訴我們,空隙眼排列方法合理与否,影响 In the pit exploration project, now has a wide range of straight-line crack undercutting. In the rock burst is poor, the tunnel section of the small conditions, compared with the tapered cut, it has also fully demonstrated its superiority. However, its blasting rate is often unsatisfactory. In particular, the phenomenon of “playing drums,” “collapsing half-dead,” “squeezing dead” and “wearing glasses” (some claim they were straight-fissure-cutting four major disorders) was particularly serious when it came to catching a big rock. The reason for this situation. It is generally believed that due to too small gap eye too small, due to improper spacing of the hole. Undoubtedly, this is an important factor in the poor blasting effect, but not all. Some face hit 1 to 3 large diameter gap eyes, but also failed to ensure good blasting effect. Facts tell us that the arrangement of gap eyes is reasonable or not, the impact