以厦门新建刘塘隧道为工程背景,介绍了机械-钻爆混合开挖方法在隧道近接施工中的应用;进而通过现场爆破振动测试,探讨赋存内侧临空面条件下,爆破振速的典型时程曲线和最大振速的衰减规律.以萨道夫公式为理论基础,分别对近场测区和远场测区的最大振速进行了回归分析.结果表明:Ⅳ级围岩的α值约1.5 ～1.6,K值约为100 ～ 130;其中K值明显小于相关规程建议的取值范围,佐证了赋存临空面对减小爆破振动效应的有利影响.%The application of mechanical-drilling and blasting mixed excavation method in tunnel adjacent construction is introduced based on the newly-built Liutang tunnel project of motor train operation depot in Xiamen.Through the field test and the data analysis for blasting vibration,the typical time history curve of blasting vibration velocity and the attenuation of maximum vibration velocity under the condition of occurrence inside free face are discussed.Based on Sadov's formula,the maximum vibration velocities for near field and far field should be performed a regression angression analysis respectively.The result shows that the c value and the K value for surrounding rock of grade ⅣV are 1.5 ～ 1.6 and 100 ～ 130 respectively.The K value is far less than the value range suggested by relative codes,which implies that the occurrence free face does relieve the blasting vibration effect significantly.
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