Fatigue Limit State of Orthotropic Steel Plate and Steel Fiber Reinforced Concrete Composite Bridge Deck

This study investigates the fatigue Performance and failure mechanism of the bridge deck composed of orthotropic steel plates acting compositely with the ovcrlaid steel fibcr reinforced concrete (SFRC) pavement. The Lingang Changjiang River Bridge of the Intercity Railway of Southern Sichuan is used as a casc. A full-scale mockup was prepared for fatigue tests. The fatigue Stresses and Cracking condition of the critical details of the mockup were simulated in ANSYS, and the failure modes of the bridge deck at fatigue limit State were analyzed considering varying values of design Parameters, including the thickness of steel plates, arrangement of studs, and the tensile strength and thickness of SFRC pavement, the values of the primary control Parameters were suggested. 1t is concluded that the measured maximum crack width in the mockup is 0. 136 mm aftcr 2 million load eyeles, and the cracks arc in the upper edge of SFRC pavement, and no cracks are observed in steel components, indicating that the fatigue Performance of the composite deck is sound. The fatigue limit State of the composite bridge deck is mainly controlled by the Cracking of SFRC pavement, the effects of steel plate thickness and stud layout on the faügue Performance of the composite deck is minor, while the effects of tensile strength and thickness of SFRC pavement arc significant, which serve as main control Parameters. When placing a thin layer of SFRCCwith a thickness less than 50 mm) on the orthotropic steel plates, the tensile strength of SFRC should be no less than 5 MPa. When placing common SFRCCwith the steel fiber volume less than 1% and the tensile strength no less than 3 MPa)on the orthotropic steel plates, the thickness of SFRC should be over 100 mm. © 2024 Wuhan Bridge Media Co., Ltd., MBEC. All rights reserved.