PVC管聚能爆破法在水平砂泥岩隧道中的应用

Application of PVC Pipe Cumulative Blasting Method in Horizontal Sandy Mudstone Tunnel

以蒙华铁路段家坪隧道为例,分析了水平砂泥岩隧道爆破成型特点,提出了PVC管聚能爆破方法,研制出了PVC管聚能爆破装置,采用PVC管聚能爆破方法达到了预期的爆破成型效果。PVC管聚能结构方向与水平岩层层理结构基本垂直时,需减少炮眼间距,PVC管聚能爆破方法能够顾更好的控制水平砂泥岩地层隧道的超欠挖量,大部分超挖量控制在15 cm以内,最大超挖量减少了78.8%。同时若工厂规模化生产PVC管聚能结构,可以更好省时省材,提高工作效率。

Taking Duanjiaping tunnel of Menghua railway section as an example,the forming characteristics of horizontal sandy mudstone tunnel by blasting were analyzed.The PVC pipe cumulative blasting method was put forward and the PVC pipe cumulative blasting device was developed.The expected blasting and forming effect was achieved by using PVC pipe cumulative blasting method.When the direction of PVC pipe cumulative energy structure was basically perpendicular to the horizontal rock layer bedding structure,it was necessary to reduce the blasting hole spacing.The PVC pipe cumulative blasting method can better control the overbreak and underbreak amount of the tunnel in horizontal sandy mudstone stratum,and most of overbreak amount is controlled within 15 cm,and the maximum overbreak amount is reduced by 78.8%.At the same time,if the factory produces PVC pipe energy-accumulating structure in large scale,the time and materials will be saved better,and the work efficiency will be improved.