While lots of harbor structures have been constructed, some of them are reaching the ends of design service life. The number of structures at which remedial actions are required will be increasing rapidly. To meet the growing number of degraded structures, strategic maintennmce and repair methods should be implemented to realize life extension and structural performance recovery. The lifecycle cost is one of the indices to choose the most appropriate method of maintenance and repair among its alternatives. While many reports and papers have been published on the topic of lifecycle cost, most of them are related to that estimated only taking into account the loss of structural functions due to material deteriorations. To well estimate the lifecycle cost practically, structural capacity such as load carrying capacity has to be taken into account at the time of repair.
　In this paper, the load carrying capacity particularly against earthquake forces of open-type wharf was quantitatively evaluated by the results of prediction on the progress of materials deterioration. Then, the recovery of load carrying capacity by several methods of repair was designed and the recovery costs were estimated. Based on the calculated results, scenarios on the time and method of repair were discussed from the viewpoints of the degree of recovery of load carrying capacity and relevant lifecycle cost. Through the discussion, we proposed the process of decision making to choose the method of repair based on the lifecycle cost.