Abstract
Deterioration rates and accelerations of an expressway equipment system vary dependent on its type and installation location. Moreover, in the asset management of the equipment system, it is necessary to quantify the failure process at arbitrary assessment units and decide the optimal management policy. This paper proposes a two dimensional Weibull mixture hazard model in order to estimate heterogeneities among deterioration rates and accelerations of each equipment. And furthermore, the authors develop a Bayesian estimation method of the two dimensional Weibull mixture hazard model. At that time, two kinds of heterogeneities are expressed as Gamma distributions and their correlation can be described using an Archimedean copula. Lastly, the proposed model is applied to the actual inspection data of an expressway equipment system and the usefulness of the model can be discussed as a case study.
