Mechanical Behavior of Bulb Flat Rib Bolted Joints in Composite Bridge Decks

Abstract:

In order to study the mechanical properties of the bolted joint of bulb flat ribs applied in composite bridge decks， two full-scale composite deck specimens with bolted joint of symmetric splice plates were designed and submitted to fatigue and static tests. Besides， a finite element model was established to analyze the stress state of the bolted joint. The test and finite element analysis results show that the bolted joint has a high fatigue cracking resistance and the bolted connection stays sound after the given fatigue load cycles in this paper. In addition， due to the asymmetric cross-section， the bolted joint features an asymmetric flexural state， which results in a 55% higher stress level of the bottom on mid-section of the splice plate installed on the side of bulb compared to the calculated value based on the plane bending theory. Moreover， the ultimate bending bearing capacity of the cross section in the bolted joint is dominated by concrete crush and shows a large margin after the occurrence of the bolt slip.