Vibration prediction and energy analysis of slope under blasting load in underpass tunnel

In order to solve the safety problem in the construction of slope and underpass adjacent tunnel by cooperative blasting, based on the expansion project of a domestic petroleum reserve base, the formula of peak vibration velocity considering elevation effect was established, and the vibration energy attenuation mechanism of tunnel blasting along the slope surface was systematically studied by using method combining dimension derivation, field test and signal analysis. The results show that the peak value of particle velocity at the edge of the same step is larger than that at the foot of the inner slope, and there is an elevation amplification effect of vibration velocity on the local slope surface. The blasting vibration formula with relative slope H/D has high accuracy in predicting the particle vibration velocity on the slope, and can reflect the influence of slope angle on the elevation amplification effect of vibration velocity. The vibration velocity and energy decay faster in the near region and slower in the far region with the increase of propagation distance. The energy of tunnel blasting vibration is concentrated in several Sub-vibration frequency bands in the range of 0-300 Hz, and the high frequency energy decays faster along slope surface. The median of dominant frequency band decays exponentially, and the energy concentrates in the low frequency band eventually. © 2020, Editorial Staff of EXPLOSION AND SHOCK WAVES. All right reserved.