Reduction of seismic risk of infrastructure via daily management works

During recent years, the possibility that damage at the time of earthquake could change depending on the deterioration condition of infrastructure has been noted through analytical calculations. Faced with such a possibility, management policy should be optimized by internalizing the external elements of earthquake damage, evaluating the appropriateness of management policy for infrastructure, and optimizing the system. In this study, the deterioration process for infrastructure was modelled using the Markov process model, and a methodology to determine the optimal management policy is proposed by considering the two risks: i) the risk that infrastructure fails because of deterioration independent of external factors such as an earthquake, and ii) the risk of infrastructure failure at the time of earthquake, which changes due to deterioration of the infrastructure. In an example of the application, it is demonstratively shown that the optimal management policy would change in the case where earthquake risk is not considered.