Blast performance and damage assessment of square reinforced concrete (RC) panels with openings

Abstract

Reinforced concrete (RC) panels are frequently designed with door and window openings to fulfill functionality requirements such as lighting, ventilation, and access. Understanding the blast resistance of these panels with openings is critical for ensuring structural safety under blast loading conditions. This study delves into the blast response of three RC panels (2.2 m × 2.2 m ×0.13 m) through field tests using 9 kg of TNT at a scaled distance of 0.61 m/kg^1/3. The tested panels include one with a window opening, one with a door opening, and one solid panel as a reference. The experimental results noted that while all panels exhibited flexural damage, the panels with openings demonstrated a better blast resistance, owing to the opening that effectively reduced blast loads acting on the panel. At the same measurement location, the door-opening panel exhibited a 19.5 % reduction in maximum displacement and a 69.6 % reduction in residual displacement compared to the solid panel. Subsequently, finite element models were developed using LS-DYNA and verified against the experimental results. The numerical analysis highlighted that the openings altered the distributions of internal forces. A series of numerical simulations were performed to develop pressure-impulse (P-I) diagrams for panels with and without openings, basing on the UFC damage criteria. The results indicated that panels with openings exhibited less damage than solid panels. Analytical formula with best fitted parameters for constructing the P-I diagrams of the studied panels was developed for quick assessment of the panel performance under blast loadings for practical applications.