Parametric estimate of accelerated life testing of welded joints based on Weibull failure distribution

In fatigue testing of railway vehicles' structure, stress is usually increased to accelerate the testing process, so that the fatigue failure mechanism can be manifested in a shorter time. For determining the stress, the accelerated life model is key. In this paper, the fatigue life test of typical welded joints of railway vehicles is first carried out. The Weibull distribution of accelerated life model of welded joints is then used to estimate the parameters. Accelerated life parameters under 50%, 95% and 99% reliability are obtained, and the results are compared with IIW standard. It was found that the dynamic stress amplitude of vehicle welded joints is generally lower than that corresponding to 1E+07 cycles, and that the slope parameter of the model is 3.70. In addition, the constant term under 95% is 8.402E+011. The parameters of the welded joints meet the IIW standard very well in terms of the fatigue performance of the welded structures in China. This study provides a reference for future designing and testing of railway vehicles.