It is reasonable that when the service life in terms of structural safety of a deteriorating reinforced concrete (RC) building does not match the original target set by the user or owner, life-cycle maintenance strategies should be implemented. Although many systems for finding optimal maintenance strategies for RC buildings have been proposed recently, few have discussed the life prediction assessment for a deteriorating RC building and the effect assessment models for repair and retrofit. For these purposes, this paper was focused on the probabilistic assessment method of service life and life-cycle maintenance strategies.
In the service life assessment method proposed in this study, a reliability function of structural safety performance was built on the basis of the hazard rate or hazard function of a deterioration RC building during a rare earthquake. For selecting optimal maintenance strategies, probabilistic effect assessment models for repair/retrofit works (five repair/retrofit works were selected) that consider the recurrence of deterioration in repaired areas and the deterioration proceeding in unrepaired areas were developed in this research. These models reflect the effects of the maintenance strategies on the failure and spalling probability directly and can be used to estimate the life-cycle performance and cost of RC buildings.
Finally, on the basis of the effectiveness of the maintenance strategies in reducing the life-cycle cost or the minimal life-cycle cost, the optimal life-cycle maintenance strategy can also be identified by using this system; case studies were used to discuss the applicability of this system.