Abstract
A focal point of the work is to set up a methodology to evaluate and optimize a road restraints system, namely a flexible guardrail system, by accurate computer simulation. The simulation of the full crash test, which is complying with the SR EN 1317 standard, is performed by using the finite element method. A finite element model of a peculiar guardrail is developed. The crash between the moving vehicle and the guardrail is fully simulated by using Ls-Dyna, a powerful explicit integration solver. The crash parameters, such as: initial velocity, relative positions of the vehicle and the guardrail, the contact and friction between the interacting components are considered. An important target of the simulation is to develop essential elements of the simulation procedure, in the frame of the SR EN 1317 standard, in order to minimize the real test number, which are costly. The posts sustaining the guardrail are not rigidly modeled or cantilevered in the ground but permitting a slight elasticity. For the simulation of the soil-post interaction. a model that employs nonlinear springs is used. After the crash, the requested parameters (SR EN 1317) are extracted. These parameters will be used in a future optimization process.
Keywords: roadside safety, guardrail system, Ls-Dyna, crashworthiness.