基于小波变换的时-能密度法优选微差延期时间

在微差爆破工程中,能否顺利实施微差爆破的关键在于确定合理的微差延期时间。首先,利用基于小波分析的时-能密度法,通过从实测爆破震动信号中识别出各段雷管实际的起爆时刻点,得到了爆破中所用雷管的实际延期时间。其次,利用信号时-频转换技术,从实测微差爆破震动信号中分离出各分段震波。最后,通过比较各分段震波在不同延期时间下的叠加效果,可以得到微差爆破的较优延期时间。以某地下工程爆破震动信号进行分析为例,对本方法的有效性作了检验。该方法具有较高的理论和应用价值,为系统开展爆破震动危害控制和预测研究奠定了理论和技术基础。

Optimizing Delay Time Interval by the Means of Time - Energy Analysis Based on Wavelet Transform

In millisecond blast engineering,the key to achieving millisecond blast is to ascertain reasonable delay time interval.Firstly,the authors make use of time-energy density analysis based on wavelet transform,and get the real delay time by identifying the blast moment of short-delay detonators.Secondly,every sub-signal is separated from measured millisecond blast vibration signal by time-frequency domain transform techniques.Lastly,the Optimized delay time interval is obtained by comparing the superposition effect of sub-signal in different delay time interval.The effectiveness of the proposed method is verified with time-energy density analysis of millisecond blasting vibration signals in an underground project.It shows a high theoretical and practical value,and establishes a theoretical and technical foundation for the study of controlling and forecasting blast vibration damage.