An assessment of constitutive models of concrete in the crashworthiness simulation of roadside safety structures

LS-DYNA, a commercial nonlinear finite element code, is widely used for crashworthiness analysis of roadside safety structures, most of which are made of concrete materials. One of the key ingredients in a successful crashworthiness simulation of roadside safety device is the constitutive model of concrete; a reliable constitutive model should adequately represent the behavior of concrete material under any loading conditions. The performance of the four constitutive (material) models of concrete that are implemented in LS-DYNA code is evaluated first by comparing against a benchmark stress-strain relation obtained from the conventional triaxial tests. Then a vehicle-to-barrier crash test is simulated using the four concrete material models to investigate their prediction of the behavior of concrete barriers subjected to vehicular impact. The findings of the triaxial test and crash test simulations are discussed in this paper along with the pros and cons of the concrete constitutive models.