Analys The Fatigue Life Of The Semi-Trailer Of Bulk Materials

The automobile industry plays an important role in the national economy. People pay more and more attention to the output and the quality of automobile. However, poor reliability of parts of domestic automobile has become an outstanding issue. The reason is that the multiple weak fatigue parts exist on vehicle structure. Specially, there is no clear indicator of fatigue life about crucial elements. The blind using these elements creates the accident and restrict the competitive power of automobile product in market seriously. Therefore, we must carry on certification the fatigue of automotive components and carry on the analysis processing to the empirical datum. Predict the failure of the parts and the fatigue life as soon as possible, in order to promptly discover and eliminate potentially unsafe factors and avoid the fatigue damage during improvement the parts of automobile.The cement semi-trailer is the high-speed movement and the load bearing machinery. It works under in the cycle of stress. Its fatigue damage is inevitable. During analysis the body's strength and durability, experiment on the road or bench test takes longer time, costs more money and is not convenience to contrast a variety of methods. It can not be given timely feedback and suggestions for improvement proposal. The methods CAE used in this paper build an experimental platform in the virtual environment. It utilizes the multi-body dynamics, finite element method and fatigue analysis comprehensive to get durability assessment of the automobile body in a virtual bench. Compare of different options before determine design mode, and can find the weak local of the structure, provide the design department earlier period support. Shorten effectively research and experiment time, save design costs.The paper analyzed the fatigue life of the semi-trailer structure. First, it analysed the static mechanics of the semi-trailer by using software ANSYS to show that the positions of the maximum stress and strain. These positions were regarded as the location to analyze the fatigue. Second, this paper analyzed the vibration characteristics of semi-trailer by modal and compared the vibration frequency of semi-trailer with the frequency of road and the engine to avoid semi-trailer had the sympathetic vibration with the road or the engine. Third, got load spectrum of semi-trailer by using road surface condition and vehicle vibration principle. Finally used of finite element analysis software ANSYS and the amended fatigue curve to calculate the fatigue life of the semi-trailer and compared with the fatigue life of the former vehicle. Improve the structure of the semi-trailer to meet the fatigue life.