Method of Fatigue Life Estimation for Spot Welded Structures

In this paper, a new theory to obtain the nominal structural stress to the cross tension and the bending moment is described and, the method of the fatigue life estimation for the spot welding structure is proposed using this theory. Proposed method can do away with D value decision problem that is the current problem in D.Radaj's method for fatigue life estimation. Moreover, a nominal structural stress that is the fatigue strength evaluation parameter can be estimated in accuracy good, because the deformation around the nugget to which it pays attention in the spot welding structure is introduced into the analysis.