结合工程实例,对深厚淤泥爆破挤淤震动效应进行测试和分析,线性拟合得出震动速度随距离衰减规律,并从控制单段最大药量、选择合理微差时间、调整震动波传播方向3个方面对地震效应控制技术开展了试验研究。试验结果表明,这些措施可以有效地控制地震效应。控制单段起爆药量是最根本因素;在相同装药量的情况下,按照大于200ms的微差时间进行控制,最大震动速度可减小20%~30%,药包中心连线方向的震速比垂直于中心连线方向的震速低15%~25%。试验结果可为类似工程提供借鉴。
According to project example, the vibration effect due to deep and thick silt by blasting compaction is monitored and analyzed. The decay law of vibration velocity with distance by linear fitting is obtained; and experimental research in aspects of controlling single deck maximum explosions, ascertaining reasonable millisecond delay time, regulating transmission direction of vibration waves is carried out. Results show that vibration effect is effectively controlled by these measures. Controlling single deck explosions is the most basic factor; the amount of explosions should be decided by field experiment; when single deck explosions are the same, the maximum vibration velocity can decrease by 20 percent to 30 percent if we set the millisecond delay time more than 200 millisecond; and vibration velocity in the direction of explosions central line is 15 percent to 25 percent lower than that in its vertical direction. The research result may provide a model for the similar project.