A structural engineering approach to adhesive bonding longitudinal plates to RC beams and slabs

Retrofitting by plating structures has been found to be very efficient. However, tests have shown that externally bonded longitudinal plates are prone to premature debonding. Furthermore, a comprehensive study of published research has also shown that there can be large discrepancies between debonding mathematical models and tests. To overcome this problem and to allow structural engineers to adhesively bond plates with safety and efficiently, a structural engineering approach is suggested whereby many of the debonding mechanisms can be prevented by judicious detailing; this approach can be applied to tension face plates, compression face plates, side plates, U-sectioned plates, and angle-sectioned plates. Four continuous reinforced concrete beams have been retrofitted with adhesively bonded longitudinal plates and tested in order to illustrate this design approach, to directly compare the performance of longitudinal side plates with longitudinal tension face plates, to compare FRP plating with steel plating, and in particular to illustrate the effect of debonding on the sectional ductility of longitudinally plated continuous RC beams.