Damage Analysis of Urban Comprehensive Pipe Gallery Caused by Internal Gas Explosion Based on HHT

In this paper, the method of embedding piezoelectric ceramic sensors is used to test the damage of the materials and models of the urban comprehensive pipe gallery. The monitoring signal is processed by HHT method, and the frequency and energy changes of the piezoelectric signal before and after the explosion were analyzed, thus the damage characteristics of the urban comprehensive pipe gallery under the internal gas explosion are determined. The results show that in the gas explosion test inside the pipe gallery model, the waveform and peak value of the piezoelectric signal before and after the explosion did not change significantly, indicating that there was no obvious damage to the side wall of the integrated pipe gallery. However, after further time-frequency analysis of the piezoelectric signal by HHT, it is found that the dominant frequency of the piezoelectric signal after explosion has a downward trend, so it is judged that there is a small damage in the pipe gallery after explosion.