摘要
在大量现场实验基础上选择有代表意义的实际工程为背景,利用三维数值模拟方法,建立了较合理的煤--岩介质穿层爆破计算模型,获得不同位置抽放孔有效应力随时间的变化规律,分别探讨了各特定位置有效应力随距离增加而衰减的差异.计算结果表明:在计算模型条件下,复合介质孔口煤层和孔底煤层中爆破击穿范围分别为1.4和1.8 m;孔底由于受应力波的叠加和反射双重作用影响,在相同距离时孔底有效应力平均值较孔口大73%;煤--岩复合介质中煤层爆破效果优于单煤层爆破效果,在同等情况下,复合介质煤层中孔口处有效应力极值较单煤层增加17%～42%,孔底增加6%～24%.
Based on a lot of mining experiments, a representative blasting engineering was studied by three-dimensional numerical simulation. A numerieal computational model of coal-roek media was constructed for the through strata blasting. Effective stress chan- ges at different locations with time were acquired, and the differenee in the decrease of effeetive stress with increasing distance was analyzed in different gas draining holes. Numerical simulation results show that the maximum radius of the area ruptured is up to 1.4 and 1.8 m for the top and bottom of the hole in the multi-media, respeetively. The average value of effeetive stress in the bottom of the hole is 73% higher than that in the top at the same distance due to stress wave interference and reflection in the bottom of the hole. The blasting effect for a coal seam in the multi-media is better than that in a single coal seam. Under the same condition, the maximum value of the effective stress at the top and bottom of the hole in the muhi-media is 17% to 42% and 6% to 24% higher than that in a single coal seam, respectively.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2012年第6期614-619,共6页
Journal of University of Science and Technology Beijing
关键词
煤矿
爆破
应力分析
数值方法
coal mines
blasting
stress analysis
numerical methods
