Damage mechanics method is applied to studying fatigue problems of metallic structuremembers.Coupling governing equations of stress-damage field and finiteelement-additional loading method are established.Furthermore,formulas of predictingfatigue crack formation and propagation lives of structural members are derived withdamage increment as step length.Total lives of typical notched plates with various geometricalparameters,made of 2024 and 7075 are estimated.The results show that the agreementbetween theoretical S — N curves and experimental ones is very nice.This methodrequires short CPU time and can be applied to engineering practice.
