Analytical and Experimental Investigation on Corrosion-Induced Concrete Cracking

Abstract

Practical experience and observation suggest that corrosion-affected reinforced concrete structures are highly susceptible to cracking. This paper presents an analytical time to corrosion-induced concrete cracking model based on fracture mechanics. The concrete cover load-bearing capacity is proposed and is used as a fracture criterion for concrete cracking. An accelerated corrosion test has been undertaken to produce data on time to corrosion-induced concrete cracking and crack width over time. A comparison between the analytical model and experimental results on time to concrete cracking and on crack width over time shows reasonable agreement. It is found that the distribution and size of the porous zone are non-uniform which is one of the main causes for discrepancy between results. The larger the porous zone is the longer it takes for concrete cover to crack due to corrosion. Although the experimental and model results exhibit similar trend, it is also found that assuming only a single propagating crack in analytical model results in an overestimation of corrosion-induced crack width. The models presented in this paper can serve as useful tool for serviceability and durability assessment of corrosion-affected reinforced concrete structures.