Experimental investigation and design optimization on flexural behavior of new UHPC deck panel with longitudinal ribs reinforced by steel plates

Abstract

Due to high strength and superior durability, ultra-high performance concrete (UHPC) is usually used in bridge deck panels to reduce self-weight and improve the anti-cracking capacity. In this study, two schemes of the UHPC deck panel with longitudinal ribs reinforced by steel plates were investigated basing on the Binzhou Yellow River Bridge, including the design considerations and advantages. The experiments were conducted to investigate the flexural behavior of this UHPC deck panel. The experimental results showed that the steel plate can improve the anti-cracking performance and stiffness of the deck more effectively compared to conventional measures of using steel bars. Cracks developed at the position where headed studs were placed due to the weakening of cross-section by high studs. Specimens failed with the appearance of the slightly compressive crack. In addition, the experimental test was simulated by finite element (FE) model in software ABAQUS. The cracking position, load-displacement relationship and strain response of testing specimens were verified by the FE model. For the design purpose, a numerical method was established to analyze flexural behavior including the stiffness, ultimate capacity and strain. The prediction results agreed well with the test results. Further, a parameter analysis was performed and it was clear that the narrow and high rib scheme provided superior flexural properties. Compared with UHPC tensile strength, the steel plate thickness had a more significant effect on the stiffness and ultimate capacity for the specimens. Finally, the segmental FE models were developed for the Binzhou Yellow River Bridge to obtain the actual stress state of the new UHPC deck. The calculation results indicated that the maximum longitudinal nominal stress in the UHPC deck was 7.6 MPa. In addition, when the diaphragm spacing was between 3.0 m and 5.0 m, the longitudinal stress would increase by about 12% with the diaphragm spacing increasing by 0.5 m. The comparisons between the actual stress and experimental results ensured the feasibility of the design.