Research On Virtual Fatigue Test Of Welded Structure Based On Virtual Prototype Technology

Fatigue damage is one of most main damages as increasing the running speed of railway vehicle. And more and more fatigue damages happened right now.In tradition, the physical prototype of railway vehicle is needed when fatigue test has to be carried out. However, if there is not any physical prototype, predicting the fatigue life will be very difficulty. In order to overcome such problem, a new technique named as VFT (Virtual Fatigue Test) has been offered in this paper. Using this technique, predicting the fatigue life could be done on the design stage. Two conditions are discussed in order to do so in this paper. One is how to obtain the dynamical spectrum; another is how to obtain S-N dada for each weld structure. The first one is based on the finite element analysis, and the second one is based on the British Standard (BS7608:1993) or the Code of IIW. In same time, how do work step by step is discussed in this paper as well.As application of VFT, two typical engineering examples, which are welded frames, are employed in this paper to see and prove its main function. The working results indicated this new technique is very useful while selecting the best design among many designs based on the comparisons .about fatigue life.