Effect of prestressing force on flexural behavior of unbonded prestressed concrete beams strengthened by CFRP sheets

This paper presents an experimental study on the effect of prestressing force on the flexural behavior of unbonded prestressed concrete (UPC) strengthened by Carbon fiber reinforced polymer (CFRP) sheets. The testing program was carried out on nine large-scale UPC rectangular beams. The investigated parameters included the reduction of prestressing force (0%, 15%, and 30%) and the number of CFRP layers (0, 2, and 4 layers).