爆炸荷载作用下小口径炮孔堵塞数值模拟  

Numerical Simulation of Small Hole Stemming under Blast Load

作　　者：张艳军 雷美荣 张东让 勾靖国 ZHANG Yan-jun;LEI Mei-rong;ZHANG Dong-rang;GOU Jing-guo(Building and Surveying and Mapping Engineering College,Shanxi Datong University,Datong 037003,China;Mechanical and Electrical Engineering College,Shanxi Datong University,Datong 037003,China)

机构地区：[1]山西大同大学建筑与测绘工程学院,大同037003 [2]山西大同大学机电工程学院,大同037003

出　　处：《爆破》2023年第2期76-80,共5页Blasting

基　　金：山西省高等学校科技创新项目(2020L0492);山西省科学技术发展计划(工业)项目(20140321003-05);教育部产学研协同育人项目(202102415008);大同市重点工业研发计划项目(2018027)。

摘　　要：针对煤矿井下炮孔堵塞密封性差甚至不堵塞所导致爆破效果不佳的问题,在分析破岩机理和堵塞机理的基础上,采用数值模拟和实验研究的方法对爆炸荷载作用下小口径炮孔堵塞进行了研究,运用了有限元分析软件建立了3 m×3 m的二维混凝土断面模型,炮孔直径为0.04 m,炮孔深度为1 m,采用柱形连续装药,卷装乳化炸药装药重量为0.3 kg,堵塞材料为砂土。炸药、混凝土体、砂土均采用Lagrange网格建模,空气采用Euler网格建模,使用ALE算法分别模拟出爆炸荷载作用下单孔堵塞长度分别为0、200 mm、400 mm的爆炸应力云图和损伤云图。结果显示:在爆炸的大部分时间里,有堵塞炮孔周边的最大应力明显高于无堵塞情形。有堵塞炮孔周边损伤程度与无堵塞情形相比,更严重,破碎块体更小。该数值模拟方法可为井下钻孔爆破分析提供一种借鉴。在对井下常用的粘土+水炮泥结构利弊分析基础上,设计研发了胀管式注水炮孔堵塞结构,现场应用效果良好。胀管式注水结构可以替代粘土+水炮泥结构应用于煤矿井下爆破中。Aiming at the problem that the blasting effect is not good due to poor or even no stemming of blast holes in underground coal mine,numerical simulation was used to analyze the mechanism of rock breaking and stemming mechanism.A 3 m×3 m two-dimensional concrete model with blast hole diameter of 0.04 m and hole depth of 1m was established using the finite element analysis software.In addition,the continuous emulsion explosive charge was set as 0.3 kg,and the stemming material was set as sand.For the explosive simulation,concrete and sand were modeled by Lagrange grid,and the air was modeled by Euler grid.ALE algorithm was used to simulate the explosion stress nephogram and damage cloud maps with a single hole stemming length of 0 mm,200 mm and 400 mm respectively under the blast load.The results show that the maximum stress around the hole with stemming is significantly higher than that without stemming.Meanwhile,the damage degree around the hole with stemming is more severe with smaller fragments than that without stemming.On the basis of analyzing the advantages and disadvantages of clay and water stemming structures commonly used in underground mines,a stemming structure by expansion-pipe water injection was designed,which can replace the clay and water stemming structure in underground coal mine blasting as a good field application.

关 键 词：小口径 炮孔 爆破 堵塞 

分 类 号：TD235.2[矿业工程—矿井建设]