OPEN ACCESS
The development of predictive tools, such as finite element models, to calculate the response of structures subjected to vehicle-borne explosive loads has become increasingly important for the engineering and defence communities. Typically, the development of such methodologies is driven by conclusions that have been obtained via field tests; however, collecting data throughout such experiments can be problematic due to the harsh testing environment. Utilizing the University of California, San Diego Blast simulator, which can simulate explosive loads in a controlled laboratory setting, a series of experiments were conducted to investigate the performance of steel columns subjected to vehicle-borne threats and a computational model was created using the qualitative and quantitative findings from the experiments. This paper describes, in detail, the development and calibration of the finite element model, initially discussed in, created from 17 blast simulator experiments that were validated against field tests. The finite element analysis was performed with LS-DYNA, a three dimensional, explicit, Lagrangian finite element code that uses a central difference time integration method from Livermore Software Technology Corporation. The model incorporated constitutive models to represent material behaviors of interest, specifically those with strain rate effects. Loading of the column was modeled using a previously calibrated low-density foam model and smooth particle hydrodynamic elements, where appropriate.
blast, columns, finite element, LS-DYNA, simulator, steel
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