露天深孔台阶爆破振动特征分析及安全控制

Characteristics analysis and safety control of open-pit deep-hole bench blasting vibration

为了分析爆破振动作用下露天开采临近巷道稳定性问题,开展爆破振动监测试验。通过对矿山工程概况和爆破参数的调查,设计监测方案,统计分析监测结果。结果表明:最大爆破振速为3.53 cm/s,小于极限值5 cm/s;三个方向振速衰减方程可以较好地描述振速衰减规律;爆破振动速度随着爆心距的增大而降低,爆破振速在垂直方向衰减最快,径向次之,水平方向衰减最慢;基于各监测点的主频率在20~100 Hz之间振频分布范围较广,最大值较高;在不考虑重复导致围岩爆破损伤积累的前提下,露天开挖爆破振动不会引起平硐的破坏。

In order to analyze the stability of adjacent open-pit roadway under blasting vibration,blasting vibration monitoring test is carried out.Through the investigation of the general situation of the mine project and blasting parameters,the monitoring scheme is designed and the monitoring results are statistically analyzed.The results show that the maximum blasting vibration speed is 3.53 cm/s,which is less than the limit value of 5 cm/s;the three-direction vibration velocity attenuation equation can better describe the vibration velocity attenuation law;the blasting vibration velocity decreases with the increase of the blast center distance,and the blasting vibration velocity decays the fastest in the vertical direction,followed by the radial direction,and the slowest attenuation in the horizontal direction.Based on the main frequency of each monitoring point,the oscillation frequency distribution range between 20-100 Hz is wide,and the maximum value is higher;under the premise of not considering the accumulation of blasting damage caused by repetition,the blasting vibration of open-pit excavation will not cause the damage of the flat shaft.