Method for predicting fatigue life of weld joint under any stress ratio based on dissipated energy

The invention discloses a method for predicting the fatigue life of a weld joint under any stress ratio based on dissipated energy, and belongs to the field of weld joint fatigue life calculation. Theobjective of the invention is to solve the problem of characterization and prediction of the fatigue life of a weld joint with any stress ratio under limited test data. According to the principle, aweld joint infrared thermal image fatigue test with the stress ratio being-1 is carried out, a weld joint dissipation energy fatigue life model is obtained, then the temperature rise of the weld jointin the stable stage under any stress ratio is tested, the stress amplitude is corrected through a Goodman method, and then life prediction is carried out according to the weld joint dissipation energy fatigue life model. According to the method, the fatigue life of the weld joint under any stress ratio can be predicted through the weld joint dissipation energy fatigue life model with the stress ratio of-1. The method has t