Nonlinear Dynamic Analysis of Steel Plates Subjected to Explosive Loading Considering the Membrane Effect and the Influence of the Negative Phase

Abstract With the increasing occurrence of explosive phenomena around the world, resulting from either armed conflicts or accidental occurrences, it becomes essential to conduct a more specific analysis of the dynamic behavior of structures subjected to this type of loading. The explosive phenomenon generates a positive pressure wave (positive phase) followed by a negative pressure wave (negative phase), which has been overlooked in past studies. However, recent works have highlighted that the negative phase can cause considerable displacements and stress at scaled distances greater than 8 m/kg 1/3 , thus proving to be as important as the positive phase. The study in question investigates the impact of explosive loading on simply supported plates, employing Kirchhoff's theory and incorporating the effect of a laterally immovable membrane when introducing geometric nonlinearity. The loading was calibrated using the software DYNABlast 1.1 (2024), developed based on Von Karman's SDOF analytical model, was carried out in relation to the results of numerical simulations performed using the finite element software ABAQUS 6.14‐1. Parametric dynamic analyses were then conducted in ABAQUS 6.14‐1 with the application of three types of loading, considering the positive phase only, the positive followed by a cubic polynomial negative phase, and the extended positive phase. Results were obtained for various explosive masses and scaled distances, providing an understanding of how the negative phase influences structural behavior in different scenarios.