Fatigue Test on Full-scale Orthotropic Steel Bridge Deck

Based on an orthotropic steel deck of a long-span cable-stayed bridge,a full-scale fatigue test was carried out for researching the fatigue behavior of critical details in steel bridge decks.The load cycle had reached 10.2 million when the fatigue test was completed.The results show that fatigue cracks are found at the rib-to-deck details and also at weld toe of rib-to-diaphragm which expand along rib web;due to the welding residual stress,cracks are found in the compressive zone of rib-to-diaphragm;however,none is found in the cutout of diaphragm;based on the stress change criterion,the fatigue detail of rib-to-diaphragm satisfies the category D of AASHTO Specification and the category 63 of Eurocode while the fatigue detail of rib-to-deck is more than the category D of AASHTO Specification and the category 71 of Eurocode;if fatigue crack observation rule is adopted,the fatigue detail of rib-to-diaphragm is higher than the category D of AASHTO Specification and the category 80 of Eurocode.