ANALYTICAL STUDY FOCUSING ON STRESS TRIAXIALITY ON FACTOR OF BRITTLE FRACTURE DURING EARTHQAKES IN STEEL BRIDGE BENTS

Abstract

  This study investigated on the cause of brittle fracture during earthquakes from the viewpoint of structural peculiarities focusing on the stress triaxiality. The target structure is the actually fractured steel rigid bent of a highway bridge. From the investigations using nonlinear finite element analysis, it was confirmed that high stress triaxiality was generated at a point supposed as fracture origin depending on the geometry of weld bead, in which the level of stress triaxiality at the point increases in the case of bead toe radius is small or two bead leg lengths are unequal.