| The primary purpose of this work is to evaluate and to improve the response of guardrail system during a lateral impact. The problem was analyzed in the first step at the component level, which consists of a single post embedded in a cohesionless soil and laterally loaded by an impactor. The lateral post response was evaluated during static and dynamic loading using a theoretical formulation able to predict the lateral load in static and dynamic modes. An improved subgrade method for soil-post interaction which includes the stiffness, damping and inertia effect involved during the crash, was proposed in this thesis. The improved model serves to study the effect of different design parameters on the post response and to evaluate the interaction between these different parameters during the dynamic loading using a Design of Experiments (DoE) approach.;The results of parametric study and the Design of Experiment conducted on a single post were used to develop a new guardrail design that was implemented in a full-scale finite element model of a Chevrolet C1500 pick truck impacting a guardrail post. The new design consists of replacing the incompressible blockout by a crushable one. The results of the simulation show that the pickup truck was redirected safely with more reduced speed, less roll angle and plastic strain than those for the baseline configuration. |
