The Effect of Shot Blasting Process on Mechanical Properties and Anti-Corrosive Behavior of Steel Reinforcement

Abstract

The need to confront the problem of corrosion resistance of steel reinforcement is an issue of major importance and a perpetual challenge to the structural integrity and reliability in reinforced concrete (RC) structures. The current experimental study presents the results of the combined effect of shot blasting and coating on steel reinforcing bars in respect to their anticorrosive resistance and their mechanical behavior, at various times of exposure to corrosive environment. In the present manuscript, a comparison of different abrasive materials was primarily conducted, via electrochemical measurements (Tafel tests), to estimate the corrosion current (icorr) for each abrasive material. After the indication that corrosion resistance can be modified by shot blasting with corundum, the method of Zn85Al15 coating was chosen to further investigate the combined effect of shot blasting with coating, in terms of percentage mass loss and mechanical behavior of steel reinforcement. The results demonstrated that, upon the completion of the surface treatment process with corundum, the mechanical performance of steel bars was improved in terms of ductility. Moreover, the Zn85Al15 coating provided a satisfactory anticorrosive protection to steel bars in the entire exposure period of accelerated corrosion. The combined contribution of shot blasting and coating processes was deemed to be very encouraging and may trigger further investigation and research, for the production of a better corrosion resistance of B500c steel.