Application of HHT Method in Identification of Blasting Millisecond Delay in Tunnel

Abstract

The identification of delay of millisecond blasting is an important basis for the adjustment and optimization of blasting scheme. Based on the HHT (Transform Hilbert-Huang) theory, the millisecond delay of blasting vibration signal collected by the actual tunnel engineering is identified by the HHT method. By using the EMD (Empirical Mode Decomposition) of HHT transformation, the typical blasting vibration signal is decomposed, and the 12 IMF components of the signal are obtained. The principal component IMF4 of the signal is determined .The HHT transform of IMF4 component is carried out, and the delay time of millisecond blasting cap is accurately identified. The analysis results show that: the HHT method is reliable and accurate for the identification of millisecond blasting delay, which provides a new way for the identification of millisecond blasting delay.