A STUDY ON DEVELOPING A DUCTILE FRACTURE MODEL FOR STRUCTURAL STEELS UNDER LOW STRESS TRIAXIALITY

Abstract

 Fracture of beam-column connection or partial penetration welded section of steel structures was observed in the past strong earthquakes, where combined shear and tensile stresses are applied. However, studies on the ductile fracture under such complicated stresses are limited. In this study, experiments were carried out to reveal the ductile fracture properties of structural steels under the combined stresses. A new ductile fracture criterion to simulate ductile cracks of structural steels under low stress triaxiality, which was based on the VG model, was proposed. As a result, the ductile fracture behavior of structural steels under low stress triaxiality can be accurately predicted.