Study on the propagation law of tunnel blasting vibration in stratum and blasting vibration reduction technology

Abstract

In order to explore the propagation law of blasting vibration velocity in strata and reduce the damage caused by blasting vibration to buildings, a series of blasting vibration tests were carried out in this paper based on the Dizong tunnel project. The affected area of tunnel blasting was divided into four areas according to observed data, respectively, the dangerous zone, the warning zone, the blasting control zone, and the safe zone. The power spectral, wavelet-energy, wavelet packet energy analysis, and other signal processing were programmed with the help of MATLAB to analyze the propagation law of blasting vibration of super-large section shallow tunnel in the stratum. The results show that the maximum particle vibration velocity at the ground surface decreased with distance. The particle vibration velocity in the z-direction was larger than that in the horizontal direction. The energy of blasting vibration mainly came from the explosion in the first cut blasting. Based on the monitoring data and vibration signal analysis, a blasting vibration reduction scheme was put forward. The maximum particle vibration velocity caused by this scheme was controlled at 1.12 cm/s, and the main frequency of blasting vibration was much higher than the natural vibration frequency of the building. The blasting vibration reduction scheme could control the delayed release of blasting energy and realize the vibration missing peak of blasting vibration, which could provide a reference for similar engineering construction in the future.