露天煤矿爆破振动速度峰值衰减规律研究

Research on attenuation law of peak blasting vibration velocity in open-pit coal mine

为分析爆破振动速度峰值在露天煤矿中的衰减规律,进行了5次爆破振动监测试验,考虑不同岩石条件、岩石的完整性以及岩石的软硬程度,对爆破振动速度峰值进行萨道夫斯基公式拟合,通过回归系数研究爆破振动的衰减效应。研究结果表明:岩体由软弱的砂质泥岩变化到质地坚硬的白砂岩时,拟合系数K值从379降低至34,下降比例高达91%,说明岩石条件是影响爆破振动衰减的重要因素;同时拟合系数α值从1.8减小至1.0,说明岩石的普氏系数与爆破振动的拟合系数呈负相关关系;当岩石条件相同时,完整性好的岩体爆破振动拟合系数均大于存在节理裂隙结构岩体的爆破振动拟合系数。

In order to analyze the attenuation law of blasting vibration velocity peak in open-pit coal mine,five blasting vibration monitoring tests were carried out.Considering different rock conditions,rock integrity and rock hardness,the blasting vibration velocity peak was fitted by Sadovsky formula,and the attenuation effect of blasting vibration was studied by regression coefficient.The results show that when the rock mass changes from weak sandy mudstone to hard white sandstone,the K value decreases from 379 to 34,and the decline proportion is as high as 91%,indicating that the rock condition is an important factor affecting the attenuation of blasting vibration;meanwhileαvalue decreases from 1.8 to 1.0,indicating that there is a negative correlation between the Proctor coefficient of rock and the attenuation coefficient of blasting vibration;When the rock conditions are the same,the blasting vibration attenuation coefficient of rock mass with good integrity is greater than that of rock mass with joint fissure structure.