Bi-material fracture properties of concrete-concrete cold joints

Repair and rehabilitation of concrete structures is a common requirement in the present day maintenance of infrastructures. Many concrete structures have been rehabilitated in order to extend their service life or to restore their original strength. An interface appears whenever a repair material is applied to a structure after rehabilitation. Usually, in a repaired system, the interface is relatively weaker than the material on either side of it. The performance of the repaired system is strongly dependent on the performance of the interface. In this work, experimental investigations have been carried out to study the fracture behavior and determine the fracture properties like fracture toughness and fracture energy of interfaces formed between different grades of concrete.