Comparison of Numerical Analysis Loading Methods of RC Columns Under Near-field Explosion

To study the influence of different loading methods for numerical analysis of reinforced concrete columns dynamic response and failure modes under near-field explosion, numerical simulations were conducted for the analysis on the overpressure of RC columns under near-field explosion by using AUTODYN, and a simplified method was proposed. Based on LS-DYNA, a 3D FE model was developed to analyze dynamic response and failure mechanism of the RC columns under near-field explosion. The near-field explosive loads were loaded by three loading methods including methods the simplified load, the load blast command, and the fluid-solid coupling of "explosives-air-concrete columns". The simulation results were compared with the explosion destruction test results. The effects of different loading methods on error, computational efficiency, and memory occupied were investigated. Results indicate that the simplified load method has smaller displacement error and less memory, however, it is necessary to master two kinds of software modeling repeatedly. The load blast command loading model is simple, the calculation time is short, and the memory is small. The model is stable but the residual displacement error is large. The modeling of the fluid-structure coupled loading of the "explosive-air-concrete column" is complicated, the calculation time is long, and the memory is large, but the error is small.