ABSTRACT
A combined highway and railway steel truss bridge with upper stiffening was taken as an engineering background to explore solution of improving fatigue performance of bridge deck. For highway orthotropic steel deck in upper layer, a layer of ultra-high performance fiber reinforced cementitious composite material (UHPFRC) was composited on deck plate by gluing corrugated steel plate shear connector (CSPC). The stress intensity factor (SIF) amplitude of rib-to-deck detail was analyzed based on linear elastic fracture mechanics. Numerical fracture mechanics results reveal SIF amplitude at the crack tip is lower than the threshold of crack propagation. For railway bridge deck in lower layer, a UHPFRC layer combined with deck plate was proposed. Fatigue stress for rib-to-deck detail under muti-field coupling effect was analyzed. Results show that fatigue stress amplitude was reduced by about 40% compared with steel deck without pavement.
