Full scale experimental tests and numerical model validation of reinforced concrete slab subjected to direct contact explosion

In this work, a numerical model for analyzing the mechanical behavior of a reinforced concrete slab subjected to a direct contact explosion was developed, using the explicit finite element code LS-DYNA and facing the following issues: generation and propagation of the blast wave, interaction with the solid structure, and mechanical behavior of the slab. The different elements that constitutes the slab were modeled as deformable bodies and the constitutive model coefficients for each material, when not directly measured, were calibrated by comparison with experimental measures. To this purpose, a reinforced concrete slab used for civil buildings was loaded with three different charge of EXEM 100: 2.1, 6.3, and 10.5 kg. For each test, the blast wave pressure-time profile was measured at two different locations and the damage extension in concrete and reinforcing elements was estimated. Using the same sets of material dependent parameters, a good agreement between experimental and numerical results was found for all tested configurations. The validated numerical model provided insight into the role of different structural elements on the failure mechanisms into the slab and is a useful tool for investigating alternative loading configurations and designing potential reinforcement solutions.