Rapid Repair Technique to Improve Plastic Dissipation of Existing Chinese RC Bridges

Abstract:

A rapid repair and retrofitting technique for reinforced concrete (rc) Chinese existing bridges damaged by a strong earthquake, is proposed and tested. These bridges were designed according to Chinese codes [1] [2] [3] but with insufficient transversal steel reinforcement. The damaged rebar and concrete parts were replaced by new bar systems and concrete cast respectively. Finally, a C-FRP wrapping was applied to increase the insufficient shear strength and to guarantee the necessary ductility in plastic hinge. This repair technique is an upgrade of the one tested with very good results during a previous experimental research [4] on bridge designed according to old Italian code [5] without proper seismic details. A new bar system assures that plastic dissipation is distributed in plastic hinge only. Some pier specimens (in scale 1:6) were built with and without the new bar systems. These specimens were tested by cyclic tests at Fuzhou University lab (China) to evaluate the effectiveness of the intervention.

• Periodical: Applied Mechanics and Materials (Volume 847)
• Pages: 204-209
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.847.204
• Online since: July 2016
• Authors: Davide Lavorato*, Camillo Nuti, Bruno Briseghella, Silvia Santini, Jun Qing Xue
• Keywords: C-FRP, Dissipation, Existing R.C. Bridge, Repair, Retrofitting

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