Flexural strengthening of reinforced concrete beams with prestressed and unprestressed fabric-reinforced cementitious plates

The flexural capacity of reinforced concrete beams strengthened with fabric-reinforced cementitious plates in the tension zone can be greatly enhanced. Two contrast beams and eight strengthened beams were used to investigate the flexural performance of reinforced concrete beams strengthened with fabric-reinforced cementitious plates. Four kinds of fabric-reinforced cementitious plates with different fabric layers and prestress values were used in the eight strengthened beams. Load, deflection, midspan strain, fabric strain and crack development were recorded simultaneously during the tests. Results indicated that cracking, yielding and ultimate loads increased with the increase in the number of carbon fabric layers and prestress value. The largest increase in the ultimate load was 41% in the strengthened beams. The ductility of the strengthened beams decreased to a certain extent. A well-established analytical formula to calculate flexural capacity and deflection was proposed, and the analytical values agreed with those measured through experiments.