Experimental Behavior of Jacketed Reinforced Concrete Beams

Repair and strengthening of reinforced concrete beams is commonly carried out by “jacketing.” Jacketing is the addition of concrete and steel reinforcement (both longitudinal and transverse) to an existing beam. This paper describes an experimental investigation into the behavior of reinforced concrete beams strengthened by jacketing. Static and dynamic load tests to failure were carried out on 61 slant shear prisms and 13 jacketed reinforced concrete T-beams. The concrete used in the jacket was preplaced aggregate concrete. The strength of the bond between preplaced aggregate concrete and plain concrete was assessed by slant shear tests and a Mohr-Coulomb-type failure envelope was derived. Static failure of the beam specimens was related to this failure envelope. The beam experimental results demonstrated the importance of adequate reinforcement detailing (i.e., that full anchorage of the additional steel at simple supports and points of contraflexure and anchorage of the additional links at the top of the beam was necessary).