Numerical simulation of concrete slabs strengthened with PTFE sheets subjected to blast load

Abstract

Due to the noticeable increase in bombing activities, the understanding of the structures response against blast loads has become one of the major concerns in structural engineering. This present study investigates the blast loading hazards that can take place in concrete slabs. Concrete slabs strengthened using PolyTetraFluoroEthylene (PTFE) are used to investigate the control of the hazards. The thickness of the slabs is 200 mm. The models are exposed to a blast load equivalent to 20 Kg of TNT explosives with a standoff distance equals to 500 mm. The concrete slabs are strengthened using different thicknesses and different number of sheets. In order to investigate the effect of PTFE sheets, AUTODYN software is used to create the numerical models. Concrete is modelled using Lagrange solver while the air and TNT explosives are modelled using Euler solver. The results of the study show that PTFE sheets control concrete fragmentation and debris propagation. The use of PTFE can improve concrete resistance to one of the blast components because of its stability at high temperatures, thermal insulation, and resistance to weathering. PTFE has a wide working temperature range from −100°F to +400°F (−73°C to 204°C) in which its properties remain functional.