An investigation of random fatigue strength of K-type tubular joints and crack propagation behaviors

Random fatigue of welded K-type tubular joints subjected to axial or out-of -plane bending load is analyzed. By considering the sizes of initial surfac e cracks and material constants as random variables with some probabilistic distributions, incorporating the effect of the weld, five hundred random s amples are generated. Statistical computational results of life of crack pr opagation and effect of change of crack shape are finally obtained and comp ared with experimental data available based on a regression analysis. Meanw hile, crack propagation behaviors are also investigated.