ABSTRACT
Chloride attack is a major deterioration factor for concrete bridges in Japan. Especially, Okinawa in Japan is a region where salt attack is severe. And also, it is known that the deterioration rate caused by airborne salt attack is different from each part and member of concrete bridges. Therefore, in order to properly evaluate the life cycle cost (LCC) of concrete bridges, it is necessary to decide the appropriate repair timing in consideration of the degree of deterioration of parts and members of bridges. In this paper, a simulation method which can evaluate the deterioration of salt damage for each part and member of concrete bridge superstructures is proposed. The proposed method, which has been adopted Random Walk method as an airborne salt simulation method, enables to consider the amount of adhesion of airborne chloride ion on surface of each part and member of concrete bridge superstructures. To evaluate the accuracy of the method, a concrete bridge superstructure which was deteriorated by airborne salt in Okinawa is focused on and simulated. From the evaluation result, it is found that the simulation results were in good agreement with investigation results. Moreover, it is shown that the possibility of prediction of the occurrence timing of deterioration on each part and member of concrete bridge superstructures by using the method.
