Title: 
            Retrofitting Method for Reinforced Concrete Structures with Externally Prestressed Carbon Fiber Sheets
        
        
            Author(s): 
            Z. Wu, T. Matsuzaki, K. Yokoyama, and T. Kanda
        
        
            
                Publication: 
                Symposium Paper
            
            
                Volume: 
                188
            
            
                Issue: 
                
            
            
                Appears on pages(s): 
                751-766
            
            
                Keywords: 
                anchorage; beams; carbon fiber sheet; composite behavior; external prestressing; reinforced concrete; retrofit
            
            
                DOI: 
                10.14359/5669
            
        
        
            Date: 
            8/1/1999
        
        
            Abstract:
            In this paper, a new method to use Carbon Fiber Sheets(CFS) which is prestressed before they are bonded to the concrete surfaces based on the concept of prestressing technique is developed. A prestressing system is first designed to be suitable for strengthening existing concrete structures. An experimental program is carried out to verify the reinforcement effects of beams such as on the improvements of flexural strength, ductility, stiffness and crack resistance. To avoid the debonding failure near the ends upon releasing the pre-tensioned force, the anchorage zone are dealt with by several proposed reinforcing methods and the effects of anchorage treatments are also discussed. An effort is also made to investigate the determination of appropriate presressing stress level of CFS and structural optimization of reinforcement.