Abstract
The service life deterioration of concrete is mainly a function of the quality of cover concrete. Whereas most past designers considered the cover size and diffusion property as the key quality parameters for durability design, whereas recent research has come to the conclusion that the water penetration front is another key issue regarding cover quality that dramatically affects the service life as well as LCC of RC structures.
In this study, Cl- ion profiles, the absorption of water, and the liquid water front position along with its variation for two types of concrete, concrete from a bank protection structure located in Okinawa and slag concrete with 70% w/c ratio in the laboratory were examined. The methods of analysis were divided into three groups. Each type of concrete was analyzed with each of the methods and compared with the actual chloride profile data. It was found that optimum method of analysis depends on the type of concrete to be analyzed. A classification of concrete types along with their respective analysis methods that modifies Fick’s law of diffusion based on the behavior of stagnation of the liquid water front in concrete is proposed.
