STUDY ON THE INFLUENCE OF RESIDUAL STRESSES AND DAMAGE ON THE HYSTERETIC BEHAVIORS OF WELDED-THICK-STEEL-PLATE MEMBERS

摘要

For thick-steel-plate members,residual stresses and damage can induced by the welding process.To investigate the influences of residual stresses and damage on the hysteretic performance of welded thick-steel-plate columns,an accurate damage model was established in this paper,in which the accumulated plastic strain was added to the metal elastic-plastic constitutive relationship with the aid of ABAQUS interface UMAT.Thereafter,the hysteretic performances of box-section columns were analyzed with the proposed constitutive model.The results show that residual stresses can accelerate the plastic development of the components.But they have little influence on their ultimate strength and hysteretic behaviours owing to the redistribution of stresses.Cumulative damage in the material can lead to the stiffness degradation,reduction of the hysteretic loop area and decrease of the energy dissipation capacity.With the number of hysteretic loop increasing,damage factor became larger.Compared with the residual stresses,damage influences the mechanical properties of components more evidently.