Evaluating the Crashworthiness of Truck Rear-End Under-Run Bars: A Finite Element Analysis

Rear-end collisions involving trucks can have a direct impact on the safety of vehicle occupants, particularly due to the crashworthiness of the truck's rear-end under-run bar. These types of accidents, which occur between small vehicle and truck, contribute significantly to fatalities and serious injuries, presenting a significant public safety concern. This research paper aims to examine the collision effects on the rear-end under-run bar of a truck and its behaviour when it collides with another vehicle. The study employed the finite element method and simulated the under-run bar and impactor collisions using finite element software. The entire structure of the rear-end under-run bar had been designed, taking into account real parameters. The under-run bar structure was made of steel, and the impactor had a mass of 115kg, which resembled the mass of a motorcycle. A predefined field feature was utilized to apply a velocity of 30km/h to the impactor, which had a cylindrical shape. The element size of the mesh for the under-run bar was determined by using the mesh sensitivity technique. The simulation was tested a few times by using different sizes of elements. It is shown that the force reached a peak value of 28kN at a displacement of 68.25 mm, corresponding to the maximum under-run bar displacement. The data revealed that the energy absorbed increased from time 0.003s to 0.012s, reaching its peak value of 11.08kJ at 0.012s. The results show convincing results and prove the capability of rear-end under-run bar to be simulated and analysed using finite element simulation.