Improving performance of CFRP retrofitted RC members using rubber modified epoxy (ongoing research)

Although the method of external attachment of CFRP to the concrete members is the most effective and economical solution for strengthening and repairing concrete structure in the century, the bonding issue between CFRP and the hosting surface still a challenge for the structural engineers. Many solutions are proposed to overcome the early debonding failure in the strengthened members. This paper reports an ongoing experimental program for testing CFRP retrofitted RC beams and slabs. Fifteen RC beams of dimensions 150x250x2300mm and twelve two- way RC slabs of size 85x1670x1670mm will be strengthened using different types of epoxies, different configurations and variable number of layers of CFRP strips (MBrace-230). Rubber modified epoxy will be used for carbon fibre external attachment using wet lay-up method. Loading frame of 500 kN capacity will be used for beams testing. While for applying uniformly distributed load on the slabs a purpose built attachment will be used. The experimental results will report on the ultimate load, failure mode, mid-span deflection, strains readings in different locations and the ductility for both groups of strengthened beams and slabs. A mathematical model will be developed to predict the behavior of RC beams and two-way slabs.