Estimation of Ground Motion Parameters for Varying Geomedia Intended for Underground Blast Scenarios

Accidental and intended blast-related activities might be detrimental to structures and their personnel. The detonation of explosives for various blast scenarios induces ground shocks that cause a ground vibration, known as a blast-induced ground motion (BIGM). These vibrations can affect the facilities or structures in the vicinity; therefore, it is essential to predict the intensity of the vibrations due to BIGMs to safeguard personnel and structures. The BIGM is measured as the peak particle velocity (PPV), peak ground acceleration (PGA), peak ground displacement (PGD), and principal frequency (PF) content. These parameters depend on the charge intensity, arrival time, and wave duration, which are usually expressed as the PPV and PGA. In this study, finite-element (FE)-based numerical simulations are carried out to investigate the influence of various geomedia, such as granite, limestone, and sandstone, on the prediction of the BIGM parameters. In addition, the numerical simulation-based estimation of the PPV for different geomedia is compared with the existing code-based and empirical approaches. Therefore, a new PPV predictor equation has been proposed that is based on numerical simulations for three rock types of granite, limestone, and sandstone. This study shows the significance of the effect of the depth of burst (DOB) and charge shape on the PPV estimation. In addition, the spatial and temporal variations in the PGA are estimated for various geomedia, and the correlation equations are proposed from the numerical study, which confirms the geomedia’s significance in the PGA prediction. The geological site constants are estimated from the numerical simulations and the investigations revealed that the prediction of the geological site constant that is based on the findings is in good agreement for sandstone and limestone for lower scaled distances; however, limestone matches well with those specified in the Indian Standard (IS) guidelines for hard rock. Therefore, comparisons between various prediction models that are presented in this study could contribute to the selection of suitable PPV and PGA predictor equations for different blast scenarios and site conditions.