特殊地形条件下爆破挤淤震动效应测试与分析

Monitoring and analysis of vibration effects due to squeezing silt by blasting at a special terrain

结合特殊地形条件下爆破挤淤工程实例,进行了爆破地震效应测试与分析。结果表明:实测质点震动速度控制在规范要求的安全限度以内,拟合得到的质点震动速度衰减规律与规范提供的经验公式基本相同;爆破挤淤产生的地震波的主振频率较低,说明传播介质对地震波起到了很大的抑制作用,测点处获得的地震波高频成分衰减很快,以低频为主要成分。爆区周围建筑设施自振频率一般在10Hz以下,为避免发生共振破坏,严格控制爆破质点震动速度和加强监测是有必要的。

To monitor and analyze vibration effect due to squeezing silt by blasting,an engineering example at a special terrain was presented.Results showed that the measured vibration velocity was within the safety-judging standard that contains norm demands,and the decay law of blasting shock wave obtained by the linear regression method was mostly consistent with that from the standard.At the same time,the results discovered that the main vibration frequency of blasting shock wave due to squeezing silt by blasting was lower;this means that the spread medium has great decay action on shock wave;and the higher frequency components of shock wave measured decay quickly;natural frequency of blasting area surroundings is generally lower than 10Hz,so in order to avoid the damage caused by resonance,it is necessary to strictly control blasting vibration velocity and enhance monitoring.