The effect of impermeability providing conctrete admixtures on reinforcement corrosion

After the earthquakes in the recent years, it has been observed that, bearing capacity (load carrying capacity) standards of concrete, most commonly used construction material, are not sufficent. Even though the liquid or gaseous substances effecting the internal structure of concrete due to it's cellular structure don't damage the concrete's compressive strength at an early age, those substances causes the service life of concrete be shorter than previously calculated. Damages due to physical, mechanical and chemcial parameters in reinforced concrete structures causes the emergence of reinforcement corrosion implicitly or explicitly. Corrosion that occurs in concrete structures in time, is the revelation of reinforcement as a result of the loss of cross section in reinforcement, decrease in tensile strength of reinforcement, decrease in adherence between concrete and reinforcement, impairment of concrete cover and spalling of concrete immediately afterwards. After the study of impermeable admixtures which can be used as a measure to corrosion, two pieces of structural impermeable admixtures and two pieces of superficial impermeable admixtures were adopted. Compressive strength test, rapid chlorine permeability test, electrical conductivity test and accelerated corrosion test and mineralogical and morphological analyses were performed on 9 series of samples. At the end of the study, a decrease in voids ratio in all series was observed. Minimum capillarity coefficent value in bitumen based superficial admixtures was determined. It was obtained that the risk of corrosion was %2 lower in structural admixtures and was on avarage in cement based superficial admixtures and was on a negligible level in bitumen based admixtures. More favourable results were obtained in water impermeable concrete applications of superficial and bitumen based admixtures.