Research on Cumulative Damage Induced by Cyclic Blasting of Tuff

Abstract

This article establishes a numerical model for cumulative damage of surrounding rock that can simulate the characteristics of progressive cyclic blasting in tunnels based on explicit dynamics and “restart” technology, and conducts research on the cumulative damage law of surrounding rock induced by tunnel blasting. The results show that: (1) considering the characteristics of progressive cyclic blasting in tunnels, the degree and range of surrounding rock damage are significantly increased compared to single blasting, with an increase of about 50%; (2) the amount of damage caused by blasting in the surrounding rock follows a Boltamann function (S-shaped curve) evolution feature as the distance between the blasting centers increases. In practical applications, when evaluating the degree and range of damage to the surrounding rock at the current location, additional cumulative damage caused by adjacent footage cycles should be considered, and the damage value can be 1.5 times the damage value of the current single blasting condition