Influence of Bleeding on Minute Properties and Steel Corrosion in Concrete

Abstract

This paper presents the results of laboratory and field investigations on the influence of bleeding on minute properties and steel corrosion in concrete. Test methods such as minute compressive strength test, minute tensile strength test and minute diffusion test were performed in the laboratory to assess the effect of bleeding on minute properties of concrete. In addition, electrochemical investigations were conducted both in the laboratory and in the field to determine the influence of bleeding on the rate of steel corrosion in concrete. The various test results indicate a strong agreement between the laboratory experiment and the field investigations. The upper layer of concrete affected by bleeding exhibited weaker strength, higher permeability, lower concrete resistance, and higher oxygen permeability. Consequently, a higher macrocell corrosion rate than the microcell corrosion rate prevailed in both the vertical and horizontal steel bar and the corrosion rate was enhanced at elevated temperatures (20-40°C).