Research on the damage effect of the RC columns under explosion loads with different charge shapes by initial volume fraction method

To accurately simulate the explosion damage effect of explosive loads on RC columns and evaluate the damage degree, this study employed the initial volume fraction method (IVFM) and damage index method to investigate the damage effect of RC columns under explosives with different charge shapes. The reliability of the IVFM was first verified using experimental values. Subsequently, peak overpressure values of the shock wave calculated by the IVFM with varying mesh sizes were compared to empirical curve values. Finally, the damage effect regularity and damage assessment of the RC column under explosion loads with different charge shapes were analyzed using the confirmed IVFM. Results indicate that the IVFM is reliable and can accurately and efficiently simulate the generation process of explosion loads. The IVFM demonstrates good agreement with empirical curves, with smaller mesh sizes yielding improved simulation effects. The pressure on the RC column’s front explosion surface is highest when induced by a vertically arranged cylindrical charge and lowest when induced by a cube charge. The charge shape significantly influences the peak pressure on the structural front explosion surface. The damage index of the RC column under all four cases ranges from 0.3 to 0.6, indicating moderate damage in all scenarios. The RC column subjected to a cylindrical charge arranged in parallel exhibits the highest damage index, while the cube charge results in the lowest damage index.