【摘要】 采用动力有限元软件ANSYS/LS-DYNA,在周边眼间距E为500 mm时,对不同光爆层厚度W下泥质灰岩中爆炸应力波的传播规律进行数值模拟研究,得到不同光爆层厚度下岩石单元应力、节点振动速度的衰减规律以及与光爆层厚度的关系,分析光爆层厚度对光面爆破效果的影响。研究表明:当W≤400 mm时,巷道围岩受到的扰动强烈,在围岩远区容易产生裂隙,在近区出现超挖现象;当W=700 mm时,因应力波在相邻炮孔间不能有效迭加而无法形成贯通裂缝,由此导致光爆效果不佳而出现欠挖现象。根据本文的研究结果,在巷道爆破掘进中,当周边眼间距为500 mm时,光爆层厚度宜取W=500～600 mm,而炮眼密集度系数为0.8～1.0较合适。更多还原

【Abstract】 On the basis of periphery hole spacing E was 500 mm,propagation rules of blasting stress waves on the condition of different minimum burdens W in argillaceous limestone were analyzed by numerical simulation with ANSYS/LS-DYNA software.Attenuating characteristics of rock element stress and node velocity and the relationship with minimum burden were obtained on the comdition of different mincmum burdens.The influence of minimum burden on smooth blasting effect was analyzed.The results show that when W≤400 mm,the disturbance that roadway surrounding rock endured is obviously strong so that the surrounding rock is easy to be damaged,meanwhile the far zones produce cracks and the near zones appear the phenomenon of overbreaking.When W=700 mm,the energy of stress wave cannot be superimposed effectively in blasthole connection direction so that the rock block cannot form the through crack,therefore,the smooth blasting effect is not good and thus leads to the consequence of underbreaking.According to the research results,in blasting excavation of roadway,on the condition of E is 500 mm,minimum burden is suitable to be 500—600 mm,and the hole compression coefficient is more appropriate to be 0.8—1.0.更多还原