Evaluation of effect of plate thickness on fatigue strength of butt welded joints by a test maintaining maximum stress at yield strength

✍ Scribed by Ohta Akihiko; Mawari Toshio; Suzuki Naoyuki

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 737 KB
• Volume: 37
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(90)90022-9

✦ Synopsis

The thickness effect on fatigue strength of transverse butt welded joints was investigated by a test method which simulates the behavior of large sized welded structures having tensile residual stresses by means of ordinary narrow specimens containing a low level of residual stresses. In the test, stress range was varied from test to test while always maintaining the maximum stress at the yield strength of the base metal. The fatigue strength of 9 and 40 mm thick specimens coincided with each other in the test condition described above. Though, the fatigue strength of 40 mm thick specimens was lower than that of 9 mm thick specimens in the test at the stress ratio of 0. It is suggested that the thickness effect appeared in R = 0 test occurred from the difference of residual stresses at the toe of weld. It is also pointed out that the estimated fatigue strength by modified Goodman or Gerber relations supposing the existence of high tensile residual stress was over conservative compared with the results by the test maintaining the maximum stress at the yield strength.