EVALUATION OF THE IMPACTS OF ASPHALTED AND STEEL SPEED RAMPS ON HEAVY-DUTY TRUCK LEAF SPRINGS
This study analyses the implications of speed ramps on the structural behaviour, as well as the fatigue life and damping characteristics of heavy-duty rear-axle leaf springs positioned over asphalted and steel speed ramps, while subjected to varying induced loading conditions. The experimental data were meticulously collected and evaluated using MATLAB software. The results of the investigation demonstrate that the speed ramps exert considerable influence on both the structural integrity and fatigue life of the leaf springs. Furthermore, the analysis revealed that longer leaf springs positioned at the top experience reduced stress levels in comparison to their shorter counterparts at the bottom. This evaluation suggests that longer leaf springs endure heightened bending stress and deformation as a consequence of the elevation of the speed ramp and the associated loading capacity, thereby impacting the fatigue life of the leaf springs under the specified induced loading conditions. Moreover, the findings indicate that the deformation (stretch) of the leaf springs, instigated by the speed ramps, facilitates the absorption of shocks that would otherwise be experienced by the truck's occupants, while concurrently inducing stress and strain in the material that could diminish its lifespan over time as the truck persistently traverses that roadway. It is therefore, advisable for leaf spring manufacturers to augment the thickness of the initial three layers and the final three shorter layers on the leaf springs to enhance their capacity to absorb shocks for extended durations prior to failure resulting from frequent cyclical motions.
Heavy-duty Truck, Leaf Springs, Asphalted Ramp, Steel Ramp.