Mechanical Performance of Steel Ring Restrainers with Corrosion Damage

Abstract

The steel ring restrainer (SRR) is a novel device for bridges, the use of which has emerged in recent years to prevent the occurrence of unseating damage. However, since the restrainer is usually installed in regions with harsh atmospheric corrosive environment, it is easily corroded. To investigate the mechanical performance of SRRs with corrosion damage, corrosion patterns of SRRs under atmospheric corrosive environment were analysed, four corroded SRR specimens were fabricated and subjected to monotonic load testing. Based on the experimental results, the validity of an associated finite element (FE) model was verified. Then, 756 FE models of SRRs with general, and local corrosion damage were established to supplement the test results. The experimental and analytical results show that the general corrosion can decrease the ultimate strength, initial stiffness, and secondary stiffness of SRRs, and the local corrosion can also affect the ultimate strength of SRRs. On the other hand, general corrosion has little influence on the variation tendency of force-displacement curve and failure modes of SRRs, while the failure modes of SRRs with local corrosion are significantly affected by the local corrosion rate and regions of local corrosion. Finally, based on the results of experimental and numerical simulation, formulae for estimating the ultimate strength and ultimate displacement of SRRs with corrosion damage were derived.