چكيده فارسي :
A total of four Reinforced Concrete (RC) slabs with dimensions of 2200×1000×100 mm strengthened with two, three and four layers of Glass Fiber Reinforced Polymer (GFRP) sheets were fabricated and tested. A loading of the slabs was performed using displacement control approach. The load-deflection and failure modes obtained from the experimental test results evidently confirmed that strengthening of under-reinforced concrete slabs with GFRP considerably improve the flexural strength capacity, however, it reduces the ductility. The flexural strength for two, three and four GFRP layers increased by 67.2%, 134% and 137.2%, respectively and the ductility for two, three and four GFRP layers decreased by 1.96%, 49% and 65.5%, respectively with respect to unstrengthened slab. So increase in the number of GFRP layers increased the flexural capacity and decreased the ductility. This method of strengthening by GFRP layers for slabs is quick, effective and does not interfere with the architectural design of the structure.
