PROBABILISTIC ANALYSIS OF WELDING RESIDUAL STRESS ON FATIGUE CRACK GROWTH

The qualitative effects of residual stress parameters on fatigue crack growth are investigated using Monte Carlo probabilistic analysis technique. These parameters include the maximum residual stress, sigma(0), half-width of the tensile residual stress region, b, and the redistribution of residual stress parameter, beta. A normal distribution is assumed for all parameters considered in the investigation and fatigue life is determined using Forman equation. The results indicate that: (i) fatigue life decreases nonlinearly if the mean of random maximum residual stress and the half-width of tensile residual stress region increases; (ii) fatigue life increases nonlinearly if the rate of residual stress redistribution increases; (iii) the effects of COV of maximum residual stress, half-width of tensile residual stress region, and redistribution of residual stress on fatigue life are insignificant.