Development and analysis of a prototype car-carrier structure using the finite element method

A very common mode for transporting vehicles over land in North America is the use of truck car-carriers. This thesis describes a computer-based modeling, simulation, and validation effort to aid in the development, testing, and design improvements of the structure of a prototype car-carrier. Car-carrier structures often crack and break during service due to fatigue stress application. In addition, the large deflections on the top decks of the trailer of a car-carrier may cause considerable damage to the carrier's structure and to the loaded vehicles due to possible collisions with the carrier as well as collisions with other loaded vehicles. In this research, numerical and experimental methods are used to investigate, analyze, and improve a prototype car-carrier's structure. A finite element model of the trailer of the prototype car-carrier was developed and model validation was completed with experimental measurements taken from field tests using a truck car-carrier when negotiating a typical speed bump. Numerical computations were conducted using LS-DYNA and the simulation results were examined in LS-POST to compare the simulation results with the field test data. After an experimental/numerical comparison, local and global geometric modifications were investigated to minimize lateral structural deflections and stress/strain concentrations. It was found that the globally modified model significantly decreased stress concentrations and lateral deflections of the trailer. The investigation shows that the finite element method can provide a powerful tool for design optimization of truck car-carriers and other dynamically loaded vehicle structures.