Assessment and Repair of Reinforced Concrete Structures Subject to Rust Damage.

(1)在调查钢筋混凝土结构在使用季节和海洋环境中的损伤时，钢筋锈蚀是造成裂缝破坏的主要原因。裂缝指标的应用是控制混凝土结构锈蚀损伤的一种手段。裂缝指标定义为混凝土与钢筋的平均应变之差。结果表明，钢筋的许用应力和保护层混凝土的高质量的再生应变对防止锈蚀是有效的。(2)钢筋锈蚀结构的粘接板修补体系在维修作业中很流行。为了确定该体系的有效性和耐久性，对采用该体系修复的钢筋混凝土梁的力学性能和耐久性进行了试验研究。该系统对修复混凝土结构是有效的，但需要注意混凝土和焊接接头的含盐量。

(1) In surveying the damage of the reinforced concrete structures in using seasand and in a sea environment, there is much cracking damages due to the rust formation in reinforcing bars. The application of the cracking index, which is defined as the difference in the average strain between concrete and reinforing bar, is a means of controlling rust damage in the concrete structures. It is found taht the allowable stress for reinforcing bars and the high quality for the rensile strain of the cover concrete are effective in preventing corrosion.(2) The repair system by using bonding plate for the concrete structures subjected to rust damage is popular with maintenance operation. In order to establish the validity and durability of this system, the experimental studies on the mechanical and durable behaviour of the reinforced concrete beams repaired with this operation are carried out. The system is effective to repair the concrete structure, but it is necessary to attend to the salt content in conctere and welding joint.