Experimental tests and fatigue strength assessment of steel welded joints under bending loading according to the Peak Stress Method

The Peak Stress Method (PSM) is an engineering, FE-oriented application of the NSIF approach to fatigue design of welded joints, which takes advantage of the linear elastic peak stresses from FE analyses carried out by using coarse meshes. Thanks to the PSM, a properly defined design stress, the so-called equivalent peak stress, can be adopted to assess fatigue failures in conjunction with a previous calibrated design fatigue curve. In the present paper new fatigue test results relevant to weld toe failures have been generated by cover plates fillet-welded steel joints under bending fatigue loading. First, the experimental results have been statistically reanalysedto provide the relevant fatigue strength classes, then they have been reconverted to the equivalent peak stress, according to PSM. A good agreement has been obtained between theoretical estimations and experimental fatigue test results.