Experimental behavior of jacketed reinforced concrete beams

Repair and strengthening of reinforced concrete beams is commonly carried o ut by "jacketing." Jacketing is the addition of concrete and steel reinforc ement (both longitudinal and transverse) to an existing beam. This paper de scribes an experimental investigation into the behavior of reinforced concr ete beams strengthened by jacketing. Static and dynamic load tests to failu re were carried out on 61 slant shear prisms and 13 jacketed reinforced con crete T-beams. The concrete used in the jacket was preplaced aggregate conc rete. The strength of the bond between preplaced aggregate concrete and pla in concrete was assessed by slant shear tests and a Mohr-Coulomb-type failu re envelope was derived. Static failure of the beam specimens was related t o this failure envelope. The beam experimental results demonstrated the imp ortance of adequate reinforcement detailing (i.e., that full anchorage of t he additional steel at simple supports and points of contraflexure and anch orage of the additional links at the top of the beam was necessary).