EFFECTIVENESS OF RC BEAM-COLUMN CONNECTION REPAIR USING EPOXY RESIN INJECTIONS

Abstract

The effectiveness of a technique for the repair of reinforced concrete beam column connections, damaged due to cyclic loading, is experimentally investigated. The applied technique is mainly based on the use of thin epoxy resin infused under pressure into the crack system of the damaged joint body. Special attention is given to the examination of the repair efficiency with reference to the shear reinforcement of the joint. To achieve this purpose, the test program included 17 exterior connection specimens covering all commonly used joint reinforcing practices. Specimens were initially subjected to increasing full cyclic imposed deformation until the cycle maximum load decreased to 40% of the yield load level measured in the first cycle. After repair, all specimens were retested in the same way. Conclusions concerning the effectiveness of the applied repair technique, based on maximum cycle toads, loading stiffness, and hysteretic energy absorption capabilities of the tested specimens, are drawn and commented upon. Remarks concerning the influence of different design reinforcement arrangements on the behaviour of the joints are also included. The examined repair technique can be considered to be satisfactory, since all repaired joints exhibited equal or higher response load values and loading stiffness compared to the virgin ones, and tended to undergo more full loading cycles without a significant loss of strength.