Study of mechanical properties of corroded steels embedded concrete with the modified surface length

• Different bar lengths are corroded and tested to tensile strength.
• The length of a corroded rod is a determining factor for all the parameters studied.
• The slope of tendency lines increases as the corroded bar length increases.
• The use of ductility criteria based on the concept of equivalent steel is appropriate.
• The values of ductility are greater with smaller corroded rod lengths.

This paper studies the effect of corrosion on the mechanical performance of steel embedded in reinforced concrete when different bar lengths are corroded. On seventy-two corrugated steel bars B500SD (with high ductility properties) that had been previously subjected to an accelerated corrosion process, corrosion was located in three different bar lengths that were tested to tensile strength. The influence of corrosion on the mechanical properties of the steel was assessed considering them individually and in relation to the concept of equivalent steel. The results obtained show that (i) significant variations are produced in the stress-strain curve obtained in tensile strength tests, even with corrosion degrees below 1%; (ii) the use of the equivalent steel concept is advantageous; (iii) the length of the corroded rod influences the value of the properties analyzed and their evolution.