Study on Misfire Identification by Time-energy Density Analysis Based on Wavelet Transform

Misfire in millisecond blasting is usually difficult to be identified for some reasons.But the blasting load will make the signals jump at the very time when it takes place.Based on this,a new method to identify the misfire is put forward by using the abrupt change of signal energy prominently.By timely analyzing the blast seismic signals monitored in field,the energy distribution of signal varying with time and frequency can be obtained with this method.The moment of peak value of energy density in the graphic is just the real blasting moment of short-delay detonators.Through contrasting the moment with the designed delay time of detonators in millisecond blasting,the exploded or unexploded detonator can be judged quickly,thus the failed hole in millisecond blasting and the position of unexploded charges can be identified.A successful application of this method has been made on site now.