Impact of target reliability of durability design on maintenance cost of reinforced concrete members in chloride environment

摘要

In reliability-based durability design of reinforced concrete (RC) structures, the depassivation of reinforcing steels is often taken as the durability limit state, and the target reliability index is a key parameter controlling the long-term durability performance of RC members. This study investigates the impact of target reliability of durability design in design phase on the life-cycle performance and the maintenance cost of RC structures. For this purpose, a chloride diffusion model for steel depassivation of RC members is firstly established; and then the cost models for maintenance of RC beam members are proposed. Based on the detailed section design and the durability limit state of steel depassivation, Monte-Carlo simulation is used to calculate the reliability index for the durability design of RC beam members; and then according to the defined maintenance inventions and associated costs, the maintenance costs for the whole service life are evaluated for different durability reliability indices. Finally, the impact of target reliability of durability design on the deterioration process and the maintenance cost is discussed.