水耦合强抛掷台阶爆破技术研究  

Research on Bench Blasting by a Water-coupled and Strengthening Cast Technology

作　　者：李康贵 夏鹏 米元桃 陈明[1] 李桐 LI Kang-gui;XIA Peng;MI Yuan-tao;CHEN Ming;LI Tong(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;Sinohydro Bureau 7 Co.,Ltd.,Chengdu 610000,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]中国水利水电第七工程局有限公司,成都610000

出　　处：《爆破》2022年第2期23-29,共7页Blasting

基　　金：国家自然科学基金面上项目资助(No.51979205)。

摘　　要：径向不耦合装药可以有效降低孔壁峰值压力,从而降低粉碎区的范围,改善爆破效果,空气和水是工程中常用的两种耦合介质。基于等熵绝热膨胀理论和弹性理论,以花岗闪长岩为例,分析了空气耦合装药结构和水耦合装药结构产生的爆破荷载。理论计算结果表明:在装药直径为70 mm、炮孔直径为115 mm时,水耦合装药结构产生的准静态压力荷载和孔壁压力峰值分别是空气耦合装药结构的5.63倍、2.15倍,有利于加强岩体爆破破碎和抛掷。进一步提出了综合优化单耗分布、炮孔倾角及起爆延时参数的水耦合强抛掷台阶爆破技术,分析了水耦合强抛掷台阶爆破破岩过程。叶巴滩水电站边坡岩体开挖的工程实例证明:此技术将高陡边坡岩体台阶爆破开挖的抛掷率提高到了47.8%以上,爆后岩块平均粒径为327.3 mm,且爆破烟尘明显降低,有利于加快施工进度。Decoupled charge blasting can effectively reduce the peak pressure of the hole wall,thus reducing the range of crushing zone and improving the blasting effect.Air and water are two common coupling media used in practice.Taking granodiorite as an example,the blast loading of these two charge structures is analyzed based on isentropic adiabatic expansion theory and elastic theory.Theoretical calculation results shows that when the charge diameter is 70 mm and the blast hole diameter is 115 mm,the quasi-static pressure load and the peak pressure of hole wall produced by water-coupled charge structure are 5.63 times and 2.15 times of those produced by air-coupled charge structure,respectively,which is beneficial to strengthen the blasting crushing and throwing of rock mass.Moreover,a water-coupled bench cast blasting technology is proposed,which adopts a comprehensive method to optimize the distribution of unit consumption of explosive,blasthole inclination angle and initiation delay.Meanwhile,the process of crushing rock with this technology is illustrated.The engineering application of water-coupled bench cast blasting technology used in the excavation of slope rock mass at Yebatan hydropower station proves that this technology can evidently improve the throwing rate of rock mass to 47.8%,and the average size of rock mass after blasting is 327.3 mm.Additionally,the blasting dust is controlled.The effects mentioned above all help to speed up the construction progress.Application of related technologies can provide reference for similar projects.

关 键 词：水耦合装药 台阶爆破 抛掷率 边坡岩体开挖 叶巴滩水电站 

分 类 号：TD824[矿业工程—煤矿开采]