Behavior of Damaged Reinforced Concrete Beams Strengthened with Externally Bonded Steel Plate


Flexural strength and deformation of reinforced concrete beams strengthened with steel plates were studied in this paper. For bonding the steel plate to the beam a technique of welding steel plate to the stirrups was followed. Fifteen beams were cast and tested; nine beams were strengthened by steel plates preloaded with a fraction of the ultimate load of the control beams (three beams) and then tested to failure. Another three beams were cast and tested to failure also, strengthened and then retested to failure. The test results indicated that the process of welding is successful and can furnish the state of composite action. After strengthening, the ultimate load was increased by 1 to 17 % and by 70 to 94 % for beams strengthened with 1 mm thick and 3 mm thick steel plates, respectively. The effect of cracking due to preloading on the flexural behavior of strengthened beams was found to be not significant.