Optimal Maintenance Policy of Coastal Protection Systems  
Author Kodo Ito


Co-Author(s) Yoshiyuki Higuchi; Toshio Nakagawa


Abstract The breakwater suffered by ocean waves and its performance for attenuating wave intensity degrade. So, the periodic maintenance for recovering its performance is indispensable. Because breakwaters are gigantic and their maintenance preparations take long times, maintenances of plural neighboring portions of breakwater can be undergone simultaneously and some breakwater maintenances can be delayed. Although breakwaters are designed considering big ocean waves which are caused by annual arrivals of typhoons, they hardly consider disasters which occur once several decades to hundreds of years. Because breakwaters are destroyed greatly and they need huge costs for their recoveries in such disasters, both steady degradations and occasional disasters should be considered when breakwater maintenances are planned. In this paper, we consider optimal maintenance policies utilizing cumulative damage model. We establish the expected cost rate and discuss the optimal damage level which minimizes the expected cost rate. We consider the basic model and the delayed maintenance one, and expand them considering the disaster recovery.


Keywords Coastal protection, asset management, maintenance, optimal policy, cumulative damage model
    Article #:  24181
Proceedings ISSAT International Conference on Reliability and Quality in Design 2018
August 2-4, 2018 - Toronto, Ontario, Canada