Shear Strengthening and Repairing of Reinforced Concrete Deep Beams Damaged by Heat Using NSM–CFRP Ropes

Abstract

This study investigates experimentally the shear strengthening and repairing of reinforced concrete (RC) deep beams damaged by heat utilizing near-surface mounted carbon fiber reinforced polymers (NSM-CFRP) ropes. The main parameters adopted in this research are rope orientation (45°, 90°) and rope spacing (150 mm, 200 mm). For this purpose, ten RC deep beams were cast and tested until failure was reached. The test results showed that using NSM-CFRP ropes with various configurations significantly enhanced the shear capacity for repaired and strengthened deep beams. All the tested beams enhanced the ultimate load capacity for the strengthened beams ranging between 19% to 46%, while for the repaired beams, the values ranged between 40.8% to 64.6%. The CFRP ropes oriented at 45° recorded the highest enhancement result in shear capacity. Notably, all tested beams had a satisfactory rise in the enhancement ratio. Consequently, the economic aspect should have priority.