| Heavy trucks always being drived on the complicatedroads with adverse conditionsunder full load or overload.Soit is very easy to result in fatigue damage of the framewhich the stress is the most complex on a truck.The fatigue damage of frame will make the trucks unable to run normally, and even lead to traffic accidents. Therefore, the research on the fatigue characteristics of frame is particularly important.This paper mainly researches on the fatigue characteristics of heavy truckframe.Firstly, the parts interact with the frame is attached strain gauges, consisting of a full bridge circuit, then the dynamic loadsof the frame boundary had been received by road test, as the frame fatigue analysisload spectruminput.Secondly,paper using ANSYS software to establish a finite element model of the frame, conducted a static analysis include fullload bending, fullloadtorsion and fullloadbending-torsion working conduction.The stress and displacement contours of the frame was obtained and the strength of the frame was checked.Later theframe free modal analysis was conducted,the top ten natural frequencies and vibration mode was obtained,and a preliminary assessment of dynamic characteristics about the frame was given.Through added unitloadone by one,finite element analysis was conducted by using inertia release method.As the finite element analysis results input of fatigue analysis,frame stress distribution under single unit force loading correspond to load spectrum was obtained.Load spectrum, finite element analysis results and the S-N curve as the input, frame fatigue life analysis based on time domain was finished by using the fatigue software n Code. frame fatigue lifenephogram was obtained and dangerous node of frame fatigue life was found.Finally, the structural optimization of the frame was completed with the ANSYS software, and the fatigue life analysis of optimized frame was conduced again. The results show that after the completion of the frame lightweight design the frame still has sufficient anti-fatigue properties and reliability. |
