Development and Evaluation of Cement-Based Patching Materials for Repair ofCorrosion-Damaged Reinforced Concrete Slabs

摘要

In this study, the results of an extensive laboratory investigation conducted toevaluate the properties of concrete mixes used as patching materials to repair reinforced concrete slabs damaged by corrosion are reported. Seven special concrete mixes containing various combinations of chemical or mineral admixtures were developed and used as a patching material to improve the durabilty of the repaired slabs. Physical and mechanical properties of these mixes, such as compressive strength, static modulus of elasticity, dynamic modulus of elasticity, and shrinkage were evaluated. Durabilty-related parameters investigated included resistance of concrete to penetration of chloride ions and freeze-thaw resistance. The results generated during this research indicated that chemical and mineral admixtures improved physical, mechanical, and durability properties of repair concrete. In addition, the ability of various repair mixes to reduce the progress of corrosion was monitored using half-cell potential, polarization resistance, and electrochemical impedance spectroscopy techniques. Half-cell potential measurements provided information about the possibility of corrosion taking place on the steel surface.