复杂山体削坡爆破控制飞石方向的工程实践  

Engineering Practice of Controlling Fly Rock Direction in Complex Mountain Slope Cut Blasting

作　　者：樊永强[1] 马俊斌 焦卫宁[1] 闫高文 拜晓亮 FAN Yong-qiang;MA Jun-bin;JIAO Wei-ning;YAN Gao-wen;BAI Xiao-liang(CCCC Second Highway Engineering Company Limited,Xi′an 710065,China)

机构地区：[1]中交第二公路工程局有限公司,西安710065

出　　处：《爆破》2022年第1期95-100,共6页Blasting

基　　金：中交第二公路工程局科技研发项目(ES-QT-016)。

摘　　要：为了改善209国道恩施谭家坝段边坡削坡爆破时因边坡地质复杂、溶洞较多等而导致爆破时产生较多飞石的问题,根据周边环境特点以及削坡山体部分的具体情况,结合最小抵抗线原理、多向爆破作用控制原理和群药包共同作用原理的优点,提出了将可能的飞石引导向安全地点的方法。先以浅孔小台阶爆破为削坡主爆破创造新的侧向自由面,再进行中深孔台阶爆破。其中,浅孔爆破采取分三个小台阶顺序依次下降,以达到一次深孔台阶爆破的高度。中深孔削坡主爆破采取大间隔延时的逐孔起爆,并整体采用小炸药单耗的松动爆破、长填塞、由里向外的顺序起爆设计。坡面边缘孔依据现场情况做独立设计,严格执行侧向最小抵抗线明显小于坡面最小抵抗线,并根据削坡厚度灵活调整起爆顺序以及孔网参数。这些措施大大较低了爆破飞石的产生,有力保障了边坡下方村庄民房及厂房的安全,同时浅孔爆破也方便新增工作面,提高施工效率,可为同类型工程提供参考。Due to complex geology of the Tanjiaba slope section of Enshi National Highway 209,fly rock was generated during blasting.According to the surrounding environment characteristics and the specific situation of cutting slope mountain section,a method to guide possible fly rock to a safe place was proposed combined with the advantage of the minimum burden principle,the multidirectional blasting action control principle and the group charge interaction principle.First of all,the short-hole and small bench height blasting was used to create a new lateral free surface for the main blasting of slope cutting,and then a deep-hole bench blasting method was carried out.The slope was descended sequentially in three small benches to reach the height of a deep-hole bench blasting.In the main blasting of deep hole slope cutting,a large-interval time delay hole-by-hole blasting method was adopted,and loose blasting with small explosive unit consumption,long packing,and inside-out sequential detonation were used.In order to reduce the generation of fly rock,some necessary measures were taken,such as the slope edge holes were independently designed according to the site conditions,the lateral minimum burden was obviously smaller than the slope minimum burden,and the detonation sequence and blasting parameters were flexibly adjusted according to the slope thickness.These measures greatly reduced the generation of fly rock,and effectively guaranteed the houses and factories safety in the villages below the slope.At the same time,the short-hole blasting also facilitates the addition of new working faces,which improves construction efficiency.It can provide a reference for similar projects.

关 键 词：山体削坡爆破 逐孔起爆 最小抵抗线 爆破飞石 

分 类 号：TD235[矿业工程—矿井建设]