Numerical investigation of the response of RC columns under blast loads

Present work sets out to investigate numerically the dynamic response of reinforced concrete columns under high rate pressure loads generated mainly from far field explosions. Emphasis is given to studying the effect of the applied high rate loads on certain important aspects of structural response affecting the mechanics underlying the exhibited behaviour. Such aspects include the distribution of internal actions (e. g. compressive strain) along the element span, the load-carrying capacity, the deformation profile, the crack formation and propagation process and the mode of failure. A well-established commercial packages (ABAQUS) is employed, as it is capable of carrying out static and dynamic three-dimensional nonlinear finite element analyses while incorporating a material model enabling realistic representation of the brittle nature of concrete behaviour. The finite element model was validated against the results of a test on a reinforced concrete column subjected to a combined action of static axial load and simulated blast load. The model is then employed to study the effects of various parameters including blast intensity, the level of the axial force, the longitudinal and transverse reinforcement on the column’s structural response under blast loads. The results indicate certain similarities some parameters have on column response mainly due to their influence on its stiffness and mode of failure.