Abstract:
This paper describes the development and validation of a nonlinear finite element model of the Modified Eccentric Loader Breakaway Cable Terminal (MELT), a type of guardrail terminal, to better understand its performance during vehicle impacts. The model was created using the TrueGrid preprocessor and the LS-DYNA3D finite element software for analysis. The model's components, including the guardrail, posts, cable anchor, and other assemblies, were meticulously designed using various element types and material models, such as the piecewise linear isotropic plasticity model for the metal parts and a combination of material models for the timber posts to simulate their complex behavior and failure modes. The model's accuracy was validated by comparing its simulation results to data from a full-scale crash test involving a small passenger car, demonstrating that the simulation successfully replicates the basic phenomenological behavior of the MELT, including the crushing of the nose, post fracture, and guardrail buckling. While some quantitative differences in acceleration peaks were observed, a statistical analysis indicated that the simulated and physical events were statistically indistinguishable, confirming that the model reasonably replicates the crash test results. The authors conclude that this finite element model is a useful tool for evaluating future design modifications to the MELT before conducting costly and time-consuming physical crash tests.
