Fatigue Strength Improvement of Welded Joint by Application of Low Temperature Transformation Weld Material

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420490
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural engineering/Earthquake engineering/Maintenance management engineering
• Research Institution: Shibaura Institute of Technology
• Principal Investigator: ANAMI KENGO 芝浦工業大学, 工学部, 教授 (30272678)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 疲労強度向上 / 溶接継手 / 低温相変態溶接棒 / 圧縮残留応力

Outline of Final Research Achievements

The objective of this research project is to examin new application of low temperature transformation welding material (LTT) for improving fatigue strength of weld joints
(1)The fatigue behavior of weld root of fillet weld made with conventional weld material and LTT was experimentally compared. While siginificant fatigue strength improvement was observed in the case where crack propagated into main plate, no improvement was observed in case where crack propagated into weld bead. In this study, this difference of fatigue strength improvement was discussed by FEM focusing the welding residual stress.
(2) The application of additional welding with LTT for the boxing weld toe of attachment side was examined and large fatigue strength improvement was obtained. In addition, it was revealed that the influence of additional welding at attachment side weld toe following to the additional welding at base plate side did not affect the fatigue strength improvement at weld toe of base plate side.

Free Research Field

土木鋼構造