A NEW APPROACH TO FATIGUE-STRENGTH DISTRIBUTION FOR FATIGUE RELIABILITY EVALUATION

This paper deals mainly with the derivation of the fatigue strength di stribution as a function of number of cycles to failure. This distribu tion is derived from the S-N curve representing fatigue. The S-N curve is obtained from the number of cycles to failure at two stress levels , and these number of cycles to failure are in turn assumed to follow a log-normal distribution. For checking the viability of this distribu tion for the calculation of reliability, the stress distribution taken is a complex distribution, which has been derived elsewhere for the s tationary random loading process. For the calculation of reliability, the stress-strength interference technique is used. As the distributio ns of stress and strength obtained are generally of a complex nature, the stress-strength interference technique cannot be used to have anal ytical solutions. For this purpose, a recent technique developed to ca lculate reliability under arbitrary distributions has been used.