Simplified micromechanics model to assess constraint effect on brittle fracture at weld defects

摘要

In recent years, experimental and analytical investigations were conducted to predict the occurrence of brittle fracture from weld defects. These investigations took into account the effects of a loss of plastic constraint at the crack tips. These effects are important because many of the weld defects in beam to column connections are small cracks although the material toughness is measured using a specimen with a deep notch. This paper shows the ability of the simplified model to predict brittle fracture under low plastic constraint conditions. Fracture toughness tests of SENB specimens with deep and shallow notches were performed and theWeibull stress approach and TSM were used to consider the effects of a loss of plastic constraint on fracture toughnessfor shallow-notched specimens.