针对城市地铁区间隧道施工掏槽眼爆破所致振速大之问题，通过在掏槽眼上方600 mm处横向布置5~7个预裂孔，采用不同药包进行预裂爆破形成裂缝及裂隙区，减少、阻碍掏槽眼爆破所致振动波向上传播，从而减小预裂孔本身爆破所致振速，使振速降低。研究结果表明，采用预裂爆破，拱顶上方质点Z向振速最大，侧向质点Y向振速最大；较在循环进尺、总装药量及炮眼数目基本不变情况下，采用5孔切缝药包预裂爆破降振效果最明显；侧向采用5孔普通药包预裂爆破降振效果最明显；切缝药包预裂爆破时随预裂孔总装药量的增加，拱顶及侧向爆破振动增强。施工中应综合考虑现场实际情况，选择合理的减振措施，实现安全高效施工。

Generally, the blasting vibration of cut holes is the biggest in the blasting construction of metro running tunnel. In order to reduce the blasting vibration velocity, through horizontally arranging five to seven presplitting holes above cut holes of 600mm, the cracks and fracture zones induced by presplitting holes blasting with different charge could reduce and prevent the shock waves of cut holes blasting spreading upward, and the blasting vibration induced by presplitting holes is also small, finally the overall blasting vibration velocity was reduced successfully. The research results showd that: when adopted presplitting blasting, the largest particle vibration velocity on vault is in Z direction and the largest particle vibration velocity in crossrange is in Y direction. Compared with the original scheme, in the case of equal circulating footage, total charge and total hole number, for the vault, the effect of vibration reduction with presplitting blasting of slotted cartridge of five holes is the most obvious, but for the crossrange, the presplitting blasting of five holes generic package is the best choice; when adopted slotted cartridge to presplitting blasting, the blasting vibration on the vault and crossrange increased with the increasing of total charge of presplitting holes. The actual situation on site should be considered synthetically, the reasonable vibration reduction measures may ensure the construction safe and efficiency.