Rehabilitation of partially damaged high strength RC corbels by EB FRP composites and NSM steel bars

Abstract

In this study, a comparison has been done between the efficiency of repairing of partially damaged high strength self-compacting RC corbels using two techniques, namely are NSM steel bars and CFRP sheets. The experimental program consists of testing eleven specimens, one of which acted as a control corbel (without repairing) and the other ten are upgraded using several configurations of alignment with two damage levels (45% and 65%). The response has been discussed in terms of the first cracking load, ultimate load, maximum deflection, failure mode, loading history, crack pattern, toughness value, and ductility index. Results revealed that the NSM steel bars technique could be adopted as an adequate method within the early levels of damage whereas the EB CFRP sheet is more suitable for largely damaged corbels. Moreover, results revealed that NSM technique with the inclined, horizontal, and combined alignment yielded enhancements in ultimate load capacity of 98.6%, 55.1% and 74.2%, respectively for a damage level of 45% and 24%, 50% and 19% for damage level of 65%, respectively. Whereas, the corresponding improvement using the CFRP sheet with damage level of 45% are 52% and 50% for specimens repaired using horizontal and diagonal CFRP sheet, respectively. The respective values are 71%, 38% for damage level of 65%.