Blasting vibration effect and safety evaluation method of railway cross tunnels

Abstract

The evolution characteristics of the peak particle velocity and frequency of an existing railway cross tunnel are systematically studied. The analysis results show that there is a difference in the blasting vibration response before and after the new tunnel face is built. In this paper, a set of blasting vibration response evaluation methods that can quantitatively consider the influence of frequency by means of dimensional analysis is introduced. In addition, relevant knowledge on topics such as wavelet packet analysis, signal processing, structural dynamics, and explosion mechanics is applied to research the influence of the frequency. The research results show that the influence of the frequency on the blasting vibration response can be quantitatively analyzed by quantifying the dynamic amplification factor. To resolve the insufficiency of field monitoring, the distribution of the blasting vibration response along the entire section of the existing tunnel is studied through numerical simulation. Based on the theory of distortion energy in material mechanics, a new idea for evaluating the blasting vibration response of a cross tunnel is proposed.