Study on the effect of load level and carriageway slab thickness on fatigue performance of concrete T-girder bridges

Purpose The effects of fatigue load level and plate thickness on the fatigue performance of reinforced concrete T-beam bridges. Design/methodology/approach Fatigue load tests were performed based on the fatigue damage theory of reinforced concrete, combined with finite element model analysis. The other conditions are controlled separately, and the fatigue performance of the T-beam bridge carriageway slab under different fatigue load levels and different plate thicknesses is studied. Findings The fatigue process of the carriageway slab of a reinforced concrete T-beam bridge is divided into three stages: fatigue damage generation, fatigue damage development and fatigue failure. Under certain other conditions, as the fatigue load level increases, the fatigue damage of the carriageway slab accelerates; as the thickness of the carriageway slab increases, the fatigue resistance of the carriageway slab improves. Research limitations/implications Tests and simulations have been carried out, but have not been applied to actual engineering for the time being. Practical implications Increasing the thickness of the carriageway slab in actual engineering is conducive to improving the fatigue performance of the bridge, and heavy-duty traffic has a greater impact on the durability of the bridge. Social implications It has certain reference value for bridge design, inspection and subsequent maintenance and reinforcement. Originality/value The originality of this article lies in designing and carrying out static and cyclic load tests separately, while introducing material damage models based on a large number of references and combining finite element analysis to consider the impact of a specific factor on fatigue performance. The test and analysis results can provide reference for bridge design and inspection.