Evaluation of Cementitious Repair Mortars for Corrosion Resistance

Abstract

Repair and rehabilitation of deteriorated concrete structures are essential not only to utilize them for their intended service life, but also to assure the safety and serviceability of the associated components. A good repair improves the function and performance of the structure, thus prevents ingress of aggressive species to the steel/concrete interface and improves its durability. It is important to evaluate the performance of repair materials available for repairing the deteriorated concrete structures. This investigation was carried out to evaluate the durability characteristics of five types of modified cement based repair mortars. The corrosion resistance of the repair materials was evaluated by conducting various tests such as water absorption, rapid chloride ion penetration test, impressed voltage, 90 days ponding test, macro cell corrosion test, weight loss measurement, etc. Details of the test and their results were discussed. It is concluded that the modified cement based repair mortars formulated with different mineral admixtures (fly ash and/or silica fume) showed improved corrosion resistance.

Simulation of corrosion protection methods in reinforced concrete by artificial neural networks and fuzzy logic

“…An accelerated corrosion test under constant potential was accomplished through a DC power source, an experimental sample, and a plastic dish containing 3.5 wt.% NaCl solution, two steel plates, and a designed data logger to collect the current data of reinforced concrete every five minutes [42][43][44][45][46]. Indeed, a working electrode, reinforcement embedded in concrete as an anode, directly connected to the positive pole of the DC power source such that the auxiliary electrode, two stainless plates as a cathode, connected to the negative terminal, afterward a 30 V impressed voltage between the counter and the working electrode to fix stress is put on.…”

Investigation on Efficiency of Repairing and Retrofitting Methods for Chloride induced Corrosion of Reinforced Concrete Structures

“…These repair mortars could normally consist of more than one type of cement (special cement, like ultra-fine alumina cement), additions (silica fume, slag or fly ash), aggregates (normal, light weight and special type fillers), admixtures (such as plasticizers), air-entrainers and accelerators, polymer additives and fine polymer fibers (Saraswathy and Song [11]). The Fly Ash (FA) and Silica Fume (SF) are normally used during concrete batching to increase the density and strength.…”