Modeling of Combined Deterioration of Concrete Structures by Competing Hazard Model

In asset management of infrastructures, predicting deterioration of structures is one of an essential technique. However, in order to estimate their deterioration process with high accuracy, not only single cause deterioration but also combined deterioration appearing on for example concrete structures has to be considered. Therefore this paper addresses the competing hazard model which is possible to model complex deterioration by multiple causes, and especially focuses on that deterioration by neutralization and salt attack on concrete bridges. Specially, separately deteriorations by them are formulated by the Weibull hazard model that can express the timedependent deterioration phenomena. Employing this model, the phenomena of which deterioration probability is increasing with time can be described. Furthermore, the complex deterioration is formulated by neutralization hazard rate’s linearly affecting salt attack one.