FLEXURAL STRENGTHENING OF REINFORCED CONCRETE BEAMS WITH CARBON SHEETS

The simple-supported concrete beams reinforced with aramid FRP(AFRP) rods and carbon FRP (CFRP) sheets were tested to failure using a symmetric two-point concentrated static loading system. AFRP rods were used instead of steel reinforcing bars, and CFRP sheets were epoxy bonded to the tension face of the concrete beams to enhance their flexural strength. Moreover, a 5-cm wide strip of CFRP sheet in some places were wrapped around the web (hereafter, called "U-jacket") after the CFRP sheets were bonded. The strain distributions on AFRP rods and CFRP sheets, and flexural behavior of the beams with AFRP rods and CFRP sheets were examined experimentally. The results showed that; (1)peeling of CFRP sheets occurred near the maximum flexural movement region, (2) ultimate load and deflection of the beam with U-jackets were higher and (3) the U-jacket was a significant factor affecting the ductile behavior of beams with CFRP sheets.