PREDICTION MODEL FOR CHANGES IN REINFORCEMENT PROPERTIES DUE TO STRAIN AGEING

Strain ageing of reinforcement is one factor that can affect the future seismic performance of damaged RC buildings. In this paper, tensile tests were conducted on 84 steel reinforcement specimens and it was found that the factors that control the reduction in ductility and increase in strength of reinforcement due to strain ageing are vanadium content, ageing period, and pre-strain. Equations were proposed to predict the change in reinforcement properties due to strain ageing. Verification of the proposed models against previous studies showed that ductility was reasonably predicted while strength increase could be predicted to within a 10% error margin.