The effect of temperature and salt contamination on corrosion of reinforcing steel in OPC and blended cement concretes

Abstract

This study was conducted to investigate the effect of relatively high temperatures (25 to 70) and chloride and sulfate contamination on the reinforcement corrosion in ordinary portland cement (OPC) and blended cement concretes. To achieve the objectives of this research study, more than 500 concrete specimens were cast and tested. The effect of temperature and chloride and sulfate contamination on the compressive strength, porosity, electrical resistivity, alklinity, water soluble chloride and sulfate concentration, and corrosion of reinforcing steel was evaluated.

Results indicated that both the temperature and chloride-sulfate contamination influence the comopressive strength of OPC and blended cement concrete specimens. The compressive strength in OPC and blended cement concrete specimens was observed to decrease with increasing exposure temperature. Addition of chloride and chloride plus sulfate ions resulted in a decrease in the strength of OPC specimens, while an increase in the strength of the blended cement concrete specimens was indicated due to the addition of these salts. The cumulative pore colume in the OPC paste specimens was observed to increase with increasing exposure temperature. This trend was also observed in blended cements.