VALIDATION OF CARBONATION INDUCED CORROSION MODELS FOR INDIAN CONDITIONS

Abstract

The corrosion in reinforced concrete structures is of great concern during durability design of a structure. In northern India i.e. away from sea shore, carbonation of concrete is the main reason for corrosion in reinforced concrete structures. There are various carbonation induced degradation models in the literatures which can be used for serviceability design of structure. Many of these models are developed on the probabilistic approach according to localized environmental and other conditions which affect the carbonation of concrete. In the present study, an effort has been made to validate those models for Indian conditions. In order to validate the models for Indian conditions, in-situ data has been collected from four cities of northern India and a comparison has been made between model values and actual values of carbonation depth and significant difference has been observed. To investigate the reasons for discrepancy, sensitivity has been analysed to check the influence of different parameters on modelling. Further, regression analysis between carbonation depth, initial chloride content and equivalent cube strength of concrete has been done which shows a good correlation between them. Also, determination of residual service life of a structure has been exemplified by collecting in-situ data from structure affected by carbonation of concrete