Study on Mechanical Behavior of Negative Bending Region Based Design of Composite Bridge Deck

Steel-concrete composite decks are paved by grid beams on the superstructure of Dongping Bridge. Bridge deck grid beams consist of three main longitudinal girders, secondary longitudinal girders, main beams, secondary beams, and composite decks (which consist of profiled steel sheet, shear connectors with perfobond strips, steel rebar and concrete with steel fiber). Shear connectors with perfobond strips are designed in Dongping Bridge to improve the longitudinal shear capability between profiled steel sheet and concrete. For the performance of deck system in structural negative bending region, three typical forms of load, namely, service load, fatigue load and failure load, are applied. The results show sufficient stiffness and high load-carry capacity of the deck system. The stress of shear connectors with perfobond strips under 10000 cycles and 2.99 million cycles of fatigue load appeared to be invariable, which indicates that PBL is of good anti-fatigue performance as shear connectors with perfobond strips reaches the corresponding yield strength before destroyed, with the yield load of 359.10 kN.