INFLUENCES OF PLATE THICKENSS ON LOW CYCLE FATIGUE STRENGTH AT WELD TOES OF CRUCIFORM WELDED JOJINTS

Abstract

The purpose of this research is to investigate influences of plate thickenss on low cycle fatigue strength at weld toes of cruciform welded joints. The influences of plate thickness ranging from 25mm to 40mm on low cycle fatigue strength were investigated by bending fatigue tests under large plastic strain on cruciform welded joints, and its elasto-plastic FEM analyses. It was found that low cycle fatigue strength decrease with increasing of plate thickness due to increases of local strain at weld toes by increasing plate thickenss. Moreover, the decreases of low cycle fatigue strength were evaluated based on increases of local strain at weld toes obtained from elasto-plastic FEM analyses.