Traditional method of determining the maintenance time of a structure system was to consider it as a non-deteriorating system. Actually, the whole life-cycle of structures fits the characteristics of deteriorating system, so establishing the maintenance strategy of deteriorating system has a significant engineering meaning. Based on characteristics of the deteriorating system, the differences between deteriorating structural systems and non-deteriorating structural systems were discussed in the paper, and the mathematical availability model and optimal maintenance strategy model has been deduced for deteriorating systems. Based on reliability theory, a mechanical model of the deteriorating structure’s failure mode was established, which adopts the minimum life-cycle cost strategy as the objective function. The optimal interval check time of deteriorating structural systems was obtained. A dam in Shandong province as an example was studied, a cost-check time curve was obtained. Some useful conclusions were given through analyzing.
