Service Life and Environmental Impact Due to Repairs by Metakaolin Concrete After Chloride Attack
A Crank-Nicolson based finite difference approach is developed for numerical assessment of chloride diffusion in concrete structures with repairs. The repair by cover concrete replacement is applied at a critical time which the chloride content at a threshold depth reaches its critical value for initiation of rebar corrosion. This aims at corrosion-free condition of concrete structures. The critical time is defined as the repair time, which the CO2 due to repair concrete production and replacement processing occurs. From the study, it is found that increasing the amount of metakaolin in repair concrete by 4 % not only leads to longer service life extension after repairs and fewer repairs but also reduces the amount of CO2 by 50 %.
KeywordsService Life Chloride Content Chloride Diffusion Repair Material Concrete Production
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This research was funded by the board of higher education and King Mongkut’s University of Technology North Bangkok under the contract no. KMUTNB-GEN-58-22.
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