土中不耦合柱状装药的外部作用爆腔分析

Analysis for the Explosion Cavity of Decoupling Column Charge External Effect Blasting in Soil

基于现场爆破试验、爆炸应力波理论和爆生气体等熵方程,分析了土中不耦合垂直柱状药包外部作用的爆腔特性,将爆腔分为柱状空腔和半椭球腔两部分,并推演了柱状空腔半径和半椭球腔高度的理论计算公式。通过进行现场爆破试验和理论计算的对比分析,表明:柱状空腔半径比半椭球腔高度大,柱状空腔半径为8.5～15.3倍炮孔半径,半椭球腔高度为7.5～12.1倍炮孔半径。理论计算值与试验值较吻合,理论计算的柱状空腔半径的误差范围是5.2%～20.6%,理论计算的半椭球腔高度误差范围为2.0%～24.8%。同时表明:不耦合装药时药包周围空气间隙的大小对柱状空腔半径影响较大。

Based on the blasting tests,explosive stress wave theory and isentropic equation of the detonation gas,the explosion cavity characteristics of decoupling column charge external effect blasting in soil was analysed,the explosion cavity was bursted into cylindrical cavity and semi-ellipsoidal cavity,the theoretical formulas of ellipsoidal cavity radius and semi-cylindrical cavity height were deduced.According to the comparative analysis of blasting tests and theoretical calculations,the results showed that ellipsoidal cavity radius was bigger than semi-cylindrical cavity height,the ellipsoidal cavity radius was 8.5~15.3 times of hole radius,the semi-cylindrical cavity height was 7.5~12.1 times of hole radius.The calculation values were in good agreement with the experimental values,the error range of theoretical calculation for cylindrical cavity radius was 5.2% ~ 20.6%,error range of theoretical calculation for semi-ellipsoidal cavity height was 2.0%~ 24.8%.At the same time,it showed that the size of air gap around charge has important impact on the cylindrical cavity radius.