Ultra-long-life anti-fatigue design method for welding structure

The invention relates to the field of anti-fatigue design of welding structures, in particular to an ultra-long-life anti-fatigue design method of a welding structure. The invention provides an ultra-long-life anti-fatigue design method for a welding structure. The method comprises the steps that a curve of the relation between ultra-high cycle fatigue stress and fatigue life of a welding joint and base metal is obtained; establishing a function relationship between the fatigue strength weakening coefficient and the fatigue life; performing finite element analysis on different material combinations of the welding joint to obtain main strain distribution, and determining a critical value of an elastic modulus ratio of a welding seam material to a base material; and according to the critical value of the elastic modulus ratio of the welding seam material to the base metal, the corresponding welding seam material is selected by combining the function relation between the fatigue strength weakening coefficient an