The Durability Analysis And Lightweight Design Of A Heavy-truck Frame

This paper mainly analysis the fatigue life and lightweight design of a heavy truck frame by using a method which based on the combination of virtual computer aided engineering and road-test method. A road-test was designed to get the acceleration data of the truck’s three axles. Then motivated the rigid-flexible coupling model of the truck based on the acceleration data of the truck’s three axles to get the load history of the truck frame. The fatigue life of the frame was predicted by using the load history and S-N curve of the frame. Based on the results, used radial basis function and genetic algorithm to accomplish the lightweight design of the frame.At first, built the FEA model to analysis the strength and the stiffness of the frame based on bend and torsion condition. Then, accomplished the road-test by collecting the frame stress data and the axle’s acceleration data, evaluated the accuracy of the FEA model by compared the virtual simulate results and the road-test data, on the other hand, the collecting of the axle’s acceleration data has built the foundation to gain the load history of the frame.Secondly, used the modal stress recovery theory to transfer the frame into flexible part, put the flexible frame into the rigid-flexible coupling dynamic model, used the axle’s displacement data to motivate the dynamic model to get the load history of the frame, then analysis the fatigue life of the frame.Finally, used the approximation model theory, chose the beam thickness as variables, built the radial basis function of the frame fatigue life and frame mass, made the fatigue life function as a constraint, used genetic algorithm to get the optimal solution.