Abstract: This article presents the deteriorations of the concrete frame arch bridge with slant leg.The model for structural analysis is built by using a bridge analytical software.The lower security position is located by structural analysis.The reinforcement methods of humid-plastering steel plates and ordinary-plastering steel plates are proposed for different positions.The reinforcement design is proved feasible and reasonable by rechecking calculations.

Key words: bridge structure； frame arch bridge with slant leg； reinforcement design； structure analysis；