Efficient SPH-PD FSI model for blast-induced crack initiation and propagation in rocks

Abstract

In tunnel blasting engineering, drilling and blasting method remains a widely adopted and efficient technique for excavating hard rock masses. Precise control of blast-induced dynamic responses is crucial for both project safety and construction efficiency. Smoothed particle hydrodynamics (SPH) and peridynamics (PD) are widely used to simulate fluid-structure interactions (FSI). This study proposes an SPH-PD FSI model to investigate gas-rock interactions under blast loading. An index-acceleration algorithm is proposed to optimize computational efficiency during the preprocessing stage. The proposed model offers advantages in algorithmic simplicity, computational efficiency, and adaptability to significant particle spacing differences. The model was validated through representative cases. The displacement trend line (DTL) analysis and the quantitative relative displacement method were applied to elucidate the blast-induced crack initiation and propagation mechanisms. Numerical results reveal the influence of prefabricated crack angles on cracking patterns. This study offers theoretical insights into the damage evolution of rocks with prefabricated cracks under blast loading, advancing understanding of crack propagation mechanisms.