In order to reduce the blasting vibration peaks of deep tunnels close to the buildings,blasting vibration experiments were carried out several times using electronic detonators.Three typical upper step blasting vibration waveforms were selected for analysis.When setting the delay time between holes or rows,not only consider the spread time of the vibration wave from the explosion source to the measurement point,but also consider a large vibration value of crest and wave velley because of the geology inhomogeneities that absorbing vibration energy and reflected at the soft and hard interface to the measuring point.Using the peak shift reduce vibration principles,considering the single-hole blasting vibration wave spread time and the main oscillation period and the main period of the reflected wave,multiple combinations of holes and row grouping tests,the delay interval between the cutting shot and the wall hole is 7—1 2 ms,it can minimize the vibration of the subsequent reflection vibration waveform,and the delay time between the holes and between the rows should not be too large,especially when the delay time between the cutting shot and the wall holes is small,the effect is better of reduce vibration.%为了降低紧邻建筑物的深层隧道爆破振动峰值,运用电子雷管进行了多次爆破振动实验.选取3个典型的上台阶爆破振动波形进行了分析,在设置孔间或排间延时间隔时,不仅要考虑振动波从爆源到测点的传播时间,还要考虑因地质的不均匀性而吸收振动能量并在软硬交界面反射到测点形成振动值更大的波峰波谷.运用错峰减振原理,考虑单孔爆破振动波传播时间及主振周期及反射波主振周期,多次进行孔间及排间分组组合实验,得到掏槽孔和扩槽孔间延时间隔时间为7~12 ms 时,能使后续反射振动波形错峰减振到最小,且孔间及排间延时时间不宜过大,尤其是掏槽孔及扩槽孔间延时间隔时间较小时,减振效果较好.
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