Fatigue analysis of cracks at the rib-to-deck welded joint of orthotropic steel deck accounting for the influence of compressive stress in cyclic loading

摘要

This paper presents the fatigue analysis of surface cracks at the rib-to-deck welded joint of orthotropic steel deck, in which the influence of the compressive stress in the cyclic loading on the crack growth is taken into account. The stress intensity factors along the surface crack front at the rib-to-deck welded joint are evaluated efficiently by Schwartz-Neuman alternating method based on a 3D local model of the rib-to-deck welded joint containing the crack. The influence of the compressive stress in cyclic loading on the fatigue crack growth is taken into account by a reverse plastic zone model at the crack tip of a 2D fracture computational mode. The results show that the compressive stress in the cyclic loading significantly influences the growth of the fatigue cracks at the rib-to-deck welded joints. The present study also indicates that the rib-to-deck welded joint of the orthotropic steel deck meets the fatigue design requirement when the thickness of the deck plate is 14 mm.