Effect of Blasting During Tunnel Excavation on an Existing Adjacent Tunnel

In recent decades, the effects of blast loads on existing structures have gained considerable attention due to the increase in threat from various activities. Site-specific empirical relationships for calculation of blast-induced vibration parameters like Peak Particle Velocity (PPV), Peak Particle Acceleration (PPA), and Peak Particle Displacement (PPD) are commonly used for the estimation of the impact of blasting vibration on an existing adjacent tunnel. However, these relationships are not able to consider the variation in rock parameters and uncertainty of in situ conditions such as modern rock mass classifications (i.e., RMR, Q-system, RQD)... In this paper, a published blast data of various researchers in different rock sites at Croix-Rousse tunnel in France have been collected and used to propose a generalized regression model for PPV by considering the effects of rock parameters like Rock Mass Rating (RMR) system, damping ratio “”, Dynamic Young’s modulus “Ed”. By using the numerical analysis method, the proposed regression model of PPV (Empirical Formula) function of a variable and multivariate can be directly used in the prediction of blast-induced vibrations in rocks.