STRESS ANALYSIS AND OPTIMIZATION OF MEDIUM SIZE BUS ROOF FRAME USING FEM METHOD

Mass transportation has an important role in Indonesian society. The number of bus passengers for daily activities is quite high. This study carried out optimization of the roof bus frame with the constraints of the value of von Misses stress and deflection resulted from the simulation of it subjected by static loading. The material used for the roof of this medium bus is Stainless Steel 1.4003 which is a material that has low corrosion rate and high ultimate tensile strength. The optimization process carried out in this study is sizing optimization which is an optimization by increasing or decreasing the thickness of the pipe size in certain areas that have critical stress or deflection. The model of the roof was drawn using solid work software and then it was exported to Hyperwork Altair software for simulation purposes with the significant load of model. Stress and deflection resulted from simulation were used as constraints in sizing optimization to get the optimum thickness of roof bus frame that can reduce the overall mass of frame. As a result of optimization, there is a reduction of 10.49% mass of overall roof bus frame.