The Influence of Corrosion Damage on Low Cycle Fatigue Life ofReinforcing Steel Bars S400

摘要

In this study the influence of corrosion and seismic load (low-cycle fatigue LCF) in the mechanical performance of reinforcing steel bars of S400 grade with 10 mm nominal diameter was investigated. There took place 140 tensile, LCF and salt spray tests which performed on reinforcing bars in different conditions. The results show that the corrosion level and surface conditions are the main parameters which affect to the low-cycle fatigue life of reinforcing bars. Moreover, through a non-linear regression analysis of the experimental data, a model of predicting the expectancy life of the corroded rebars was conducted. This prediction was based on two models: the first model was about an imposed of (total) strain amplitudes (εα) and the second model on predicting the strength degradation per cycle of fatigue in correlation with the plastic strain amplitudes (εp). Both the experimental study and the prediction modeling conducted for the same steel grade S400 with and without ribs. The model prediction of non-linear regression analysis, show a good agreement with the observed experimental results and adequately confirmed the experimental results showing that from the first levels of corrosion, the degradation of their life expectancy was obvious as well the rebars without ribs (smoothed) which present more advanced mechanical behavior and life expectancy against to the respective ribbed rebars.