Effect of prestress level on beams retrofitted with prestressed frp sheets

Abstract

The Retrofitting is a technique of strengthening the existing structures which are unable to take the unpredicted loads and deteriorated due to environmental effect. This technique has been effectively applied on the existing structures like buildings, dams, bridges etc. There is a various existing techniques of retrofitting which are section enlargement (jacketing), bonded steel plates, strengthening with FRP composite sheets. A lot of research has been carried out for above retrofitting techniques. From all the above techniques, FRP is the most effectively used for the retrofitting. The advantages of resistance to corrosion and higher specific strength make this material ideal for reinforcing existing structures. For retrofitting the existing structures, FRP can be used by various techniques such as FRP laminates, FRP non prestressed sheets, FRP prestressed sheets, FRP wrapping and FRP reinforcement also. The amount of research conducted on retrofitting by prestressed FRP sheet is quite less. So in this thesis, the effect of different prestresse levels of FRP sheets on beams have been carried out.