Abstract: This paper develops a simple and easy fatigue damage accumulation rule, of which the key lies in finding an equivalent-cycle function that satisfies boundary conditions and sequence conditions. It is found that several main fatigue damage accumulation rules proposed in the past can be incorporated into the framework of the present rule. Based on the rule, a new formulation for the fatigue damage accumulation is obtained. By examining the correlation between the formulations and available experimental data, it w 11 be seen that the present formulation has better predictability than the linear rule of Miner and the other four.

Key words: fatigue damage, cumulative damage, life prediction