An analytical and experimental study on the thickness effect of fatigue strength in large-scale-welded models

Thickness Effect on Fatigue Strength of Welded Joint Improved by HFMI

“…It is required in the Common Structural Rule (CSR 1) ) that the fatigue strength reduction factor set to 0.25 uniformly for welded structures. However, the coefficient was decided empirically because of insufficient knowledge about the mechanism of the effect, therefore, the research 2) was carried out to investigate the factors which affect thickness effect by Class NK with the Shipbuilders' Association of Japan.…”

“…nf = 2.69, ni = 2.87 (17) log (Cf) = 12.5, log (Ci) = 12.7 (18)The fatigue test results inFigure 5are presented in terms of Seq inFigure 7. The solid line is the mean line based on equation(2).The broken line is the 97.5 % survival probability line calculated by subtracting two standard deviations of log N from the mean line.Comparing Figure 5 with Figure 7, it is clear that the modified MIL-HDBK-5 method has successfully correlated most of test results from the various types of post weld treatment without the distinction of the plate thickness including the result of the aswelded condition.…”

Fatigue failure investigation of thick plate butt‐welded joints with incomplete penetration effect

“…35 So far, the thickness effect demonstrates a modest variation of the fatigue strength in large-scale weld specimens compared with small-scale specimens. 36 Meanwhile, some researchers indicated that the current guidelines are too conservative. 37,38 However, these references evaluated the full penetration joints, and the studies about the incomplete penetration thick butt-welded joints are limited.…”