Predicting the threshold values based on diffusion model of nitrite ions in reinforced concrete

Abstract

The prediction model for inhibition effect of reinforced concrete was presented based on the Magge’s model when the concrete surface was brushed with nitrite solution. The influence of the amount of nitrite solution on inhibiting duration was also discussed through a simulation analysis when the amount of solution were 250 g/m², 500 g/m², 1000 g/m² and 1500 g/m², respectively. The experimental results confirm that nitrite ion can diffuse well in concrete to reach an effective mol ratio from the surface of the concrete to the surface of the reinforcement, and has an effective protection for the bars against corrosion. The higher the amount of solution, the better it will accelerate getting the threshold value of mol ratio on the surface of rebar, and retarding the time for loosing the effective threshold value of mol ratio. It helps to increase the tendency of inhibiting duration and prolong the life of reinforced concrete. The nitrite solution amount is used to predict the corrosion inhibiting duration of concrete that contains chloride salt.

Keywords

reinforced concrete / nitrite ion / diffusion / threshold value

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