Some aspects on fracture mechanics design of fatigue loaded welded structures

摘要

This paper summarizes the fundamental parameters affecting fatigue crack growth in welded joints such as initial crack size, stress concentrations, residual stresses and material properties.crack growth equation is proposed for the threshold and the linear region in the log-log plot of crack growth rate versus stress intensity factor range. The equation gives a better estimate of the crack growth rate than the equations commonly found in the literature.The fracture mechanics based method for life predictions is exemplified with calculation of the Detail Category (fatigue strength at 2·10{sup}6 load cycles) a cruciform joint. The results is compared to the Detail Category taken from the SwedishRegulations for Steel Structures and to experimental results.