炮孔直径对层状板岩光面爆破效果影响的研究

大孔径技术更适合层状板岩光面爆破。为了寻求合适于层状板岩光面爆破的最佳炮孔直径,应用有限元软件ANSYS/LS-DYNA对层状板岩进行模拟计算,得出爆炸应力波在该类岩体内的传播规律,结合实践经验及《爆破手册》确定大孔径光面爆破现场试验参数,以炮孔直径为单一的变量进行炮孔直径为90mm、100mm、110mm、115mm、120mm、125mm六组现场试验,并以半孔率、光面壁不平整度作为试验效果分析的判别依据。试验结果表明:在炮孔直径为115mm时,层状板岩光面爆破半孔率出现最大值峰值85.58%,层状板岩光面爆破不平整度出现最小值峰值7.16cm。综合半孔率和不平整度,炮孔直径为115mm时,层状板岩光面爆破效果最佳。

Study on Effect of Hole Diameter on Smooth Blasting of Layered Slate

The long-term practice shows that the large aperture technology is more suitable for smooth blasting of layered slate.In order to determine the optimal hole diameter,the blasting test of layered slate was simulated with ANSYS/LS-DYNA.As result,the propagation behavior of explosion stress wave in rock mass was obtained.According to practical experience and blasting manual,the field test parameters of large aperture smooth blasting were determined.Taking the hole diameter as the only variable,six groups of the field tests were carried on with hole diameters 90 mm,100 mm,110 mm,115 mm,120 mm and 125 mm,respectively.The semi-hole rates and smooth wall roughness were taken to evaluate the blasting effect.The test results show the case with hole diameter 115 mm,the biggest semi-hole rate is obtained as 85.58 %,and the minimum roughness is 7.16 cm,where the optimal smooth blasting effect is achieved.