Mechanical Behavior of Preloaded Reinforced Concrete Beams Strengthened by Pretensioned Carbon Fiber Composite Sheets

Abstract:

According to the characteristic of preloaded reinforced concrete beams strengthened by pretensioned carbon fiber composite sheets,a suitable finite element model and corresponding calculation steps were proposed.The method was verified by the testing results of two groups of strengthened beam specimens.Comparison between simulation and testing results shows that the proposed method is a precise numerical tool.Further parameter analysis using the proposed method shows that the bearing capacity of a strengthened beam might be notably reduced if the preload applied on the beam is larger than 40% of the initial bearing capacity of the beam,the strength of carbon fiber composite sheets can be fully used by using pretensioning technique,and the negative influence of the preload on the bending behavior of a strengthened beam can be made up when the prestrain of carbon fiber composite sheets is between 0.003~0.004.