Shear behaviour of pre-cracked continuous beam repaired using externally bonded CFRP strips

Abstract

Shear failure usually occurs suddenly and without any warning Historically, the strengthening and repairs of existing concrete structures have been done by using conventional techniques such as externally bonded steel plates, steel or concrete jackets and external post-tensioning. However, these conventional techniques have some problems regarding their maintenance where a steel plate has the risk of corrosion due to the environment. As this problem arises, a lot of studies have been carried out to find a solution to overcome the problem. Therefore, an application of composites material has been emphasized to extend the service life of existing concrete structures. In this research, CFRP composite was used as repair material method for continuous beams. A total of five beams were fabricated and tested includes one control specimen while the other four beams were wrapped with CFRP strips. Experimental results shows that beams repaired using CFRP strips achieved higher shear capacity compared with control beam by 18% to 44%. Comparison of the experimental results with theoretical study using existing model also shows good agreement. It shows the effectiveness of CFRP strips in enhancing shear capacity of cracked continuous beam.