Finite element modeling of FRP retrofitted RC column against blast loading

摘要

Fiber-reinforced polymer (FRP) wrap could considerably improve the shear capacity and ductility of RC columns. FRP is therefore considered a potential material to strengthen the RC column against blast loading. Due to the high expense and safety concern of field blast tests, a very limited number of explosion tests on FRP retrofitted RC columns have been conducted, which hinders the understanding of the response of FRP retrofitted RC columns against blast loading. With advanced computational technology, it is convenient to develop a Finite Element (FE) model that can accurately capture the structural response of FRP retrofitted columns under blast loading. In this paper, a refined FE model was established to simulate the FRP retrofitted RC columns under blast loading. Strain rate effects on the concrete and steel reinforcing bar as well as the FRP composite of which the strain rate effect was commonly ignored, were all considered in the model. Comprehensive modifications were made to the Karagozian and Case concrete (KCC) model to accurately capture the mechanical properties of FRP-confined concrete. Finally, the FE model was validated with several available experimental tests. The developed FE model could capture the blast response of FRP retrofitted columns with good accuracy.