露天爆破堵塞物对混装乳化炸药影响研究  

Effect of Stemming on Mixed Emulsion in Open-pit Blasting

作　　者：邹成铭 黄刚[1] 张建华[1] 王强[2] 李宁[1] ZOU Cheng-ming;HUANG Gang;ZHANG Jian-hua;WANG Qiang;LI Ning(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;Mining Branch of Jinduicheng Molybdenum Co.,Shanxi 714102,China)

机构地区：[1]武汉理工大学资源与环境工程学院,武汉430070 [2]金堆城钼业股份有限公司矿山分公司,陕西714102

出　　处：《爆破》2023年第3期101-107,共7页Blasting

基　　金：国家自然科学基金项目(42271296)。

摘　　要：随着现场混装乳化炸药的广泛应用,露天爆破施工中存在着堵塞物渗入乳化炸药,间接改变堵塞长度,降低爆破效果的情况。为研究露天爆破堵塞物对混装乳化炸药影响,先后开展了填塞模拟试验、数值模拟试验及现场爆破试验。首先,采用4种常用孔径的PVC管模拟炮孔,使用钻孔岩屑模拟炮孔堵塞,系统研究了填塞过程中炸药药柱顶部岩屑渗入炸药情况;其次,借助LS-DYNA软件进行单孔爆破数值模拟,通过观察测点的应力值变化,探究了药柱顶部混入堵塞物对爆炸威力产生的影响;最后,以金堆城露天台阶爆破为工程背景,在装药过程中设置物理隔离改善堵塞工艺,通过对比物理隔离前后的爆破效果分析堵塞物对混装乳化炸药的影响。结果表明:在乳化炸药填塞过程中,药柱顶部首先出现炸药上溢现象,在填装完成后受重力影响岩屑逐渐渗入乳化炸药,且随着孔径的增大,相同时间内岩屑的渗入长度不断增大;数值模拟结果表明,不同监测点位的应力值均有所下降,堵塞物的渗入降低了顶部炸药的爆炸威力;对现场爆破后的顶部岩石进行块度分析发现,对比常规装药过程,采取堵塞隔离措施后,爆区内岩石主要块度分布从20~40 cm降低为0~20 cm,且超过60 cm的岩石占比由6.13%降低至1.81%。综上,堵塞物渗入对乳化炸药的威力及爆破效果影响显著,通过采取物理隔离手段分离堵塞物与炸药可以有效改善爆破效果。With the widespread use of mixed emulsion explosives,there exists the situation that the stemming materials penetrate into emulsion explosives in open-pit blasting construction,which indirectly changes the stemming length and reduces the blasting effect.To study the influence of stemming on mixed emulsion explosives,stemming simulation tests,numerical simulation tests and field blasting tests were carried out successively.Firstly,four kinds of PVC pipes with common hole diameters were used to simulate the blasting holes,and the rock chips were used to simulate the stemming materials.They were used to systematically study the infiltration of rock chips into the explosives on top of the explosive column during the filling process of stemming.Secondly,the numerical simulations of single-hole blasting were conducted with the LS-DYNA software,and the influence of the stemming mixture at the top of the explosive column on the explosive power was investigated by observing the changes of stress values at the measurement points.Finally,the stemming filling process was improved by setting physical isolation during the charging process based on the bench blasting in the Jinduicheng open pit mine.And the effect of stemming on the mixed emulsion was analyzed by comparing the blasting effect before and after the physical isolation.The results show that the phenomenon of explosive overflow appears on the top of the explosive column in the explosive charging process.Then,the rock chips gradually infiltrate into the emulsion explosive due to the influence of gravity after the charging is completed,and the infiltration length of rock chips increases with the increase of hole diameter in the same time.The numerical simulation results show that the stresses of different monitoring points have decreased,and the infiltration of stemming reduces the explosive power of the top explosive.The fragmentation analysis of the top rock after improvements shows that the main fragment size distribution of rocks decreases from 20~40 cm to 0~20 cm

关 键 词：堵塞长度 混装乳化炸药 爆破块度 数值模拟 现场试验 

分 类 号：TD235[矿业工程—矿井建设]