A test program was designed to study the fatigue strength of longitudinal fillet welds of T-1 constructional alloy steel. The fillet welds were loaded by a uniform normal stress such as occurs in the flange-to-web fillet weld of a welded beam. Instead of testing only welded beams under cyclic loading, small, axially loaded fillet-welded specimens that simulated the fillet-welded region of the beam were designed and tested. Some constructional alloy beams of similar geometric proportions were also tested to check the correlation between the fatigue strengths of the axially loaded specimens and the beams. S-N curves were developed with axially loaded specimens for three stress ratios: ½, 0, and -1. Good correlation was observed in the fatigue tests between the tee specimens and beams welded by the automatic submerged-arc process.
"Fatigue Strength of Longitudinal Weldments in Constructional Alloy Steel," Welding Journal, v. 44, October 1965, pp 458-465.