According to the relative position between interbedded surrounding rock and the peripheral holes,the relationship between bedding planes and the connecting line of the adjacent blastholes was classified into three kinds.Mechanism for bedding planes bringing impact to crack propagation in rocks between blastholes by blasting under typical work conditions(with bedding planes on the perpendicular bisector of the connecting line of blastholes)was explored by the LS-DYNA numerical simulation;and the effect of bedding planes in a different relative position to the connecting line of blastholes on the blasting effect of surrounding rock was also studied.It is found that the propagation speed of blasting vibration waves in sandstone is slightly higher than that in sandy mudstone.Under blasting loads,the surrounding rock above both softer layer and the beddings suffer severe damage.The superposition of two-blasthole blasting vibration wave peaks intensifies the damage to the surrounding rock.The blasting effect is poor when the bedding plane penetrates the blastholes,but the blasting effect is ideal if the bedding plane is on the perpendicular bisector of the connecting line of blastholes.
关键词
隧道爆破/互层状围岩/切槽爆破/裂纹扩展/互层面/周边孔/爆破振动/围岩损伤
Key words
tunnel blasting/interbedded surrounding rock/blasting with slotted blasthole/crack propagation/bedding plane/peripheral hole/blasting vibration/surrounding rock damage
维普
万方数据