Mechanical behavior of corroded reinforcing steel bars S500s tempcore under low cycle fatigue

摘要

The results of an experimental study for assessing the effects of the gradually accumulating corrosion damage due to laboratory salt spray corrosion on the mechanical behavior of reinforcing steel bars Grade S500s tempcore, when subjected to alternating cycles in the region of low cycle fatigue are presented. The accelerated laboratory salt spray method as well as the low cycle fatigue, simulate the natural corrosion in coastal areas and the seismic loads of structures made from reinforced concrete respectively, in a satisfactory way. The low cycle fatigue test results indicate that the corroded steel bars exhibit a gradual reduction in both the load bearing ability as well as the available energy. Tensile tests confirmed the gradual occurring embrittlement due to corrosion of the steel bars. Furthermore, a reduction of the number of cycles to failure under conditions of low cycle fatigue was observed. As the two significant degradation factors corrosion and low-cycle fatigue are functions of time, it seems that the reliability of steel bars S500s tempcore is time dependent as well.