Renforcement de poutres de béton armé en cisaillement à l'aide de matériaux composites : étude comparative

Abstract

Research conducted for the past 23 years on shear behavior of concrete beams reinforced with FRP have determined some influencing parameters which today govern various international codes. Through these studies, some systems have been tested and were able to demonstrate that their use can provide a shear strength gain during the rehabilitation of deficient structures. In this study, a review of the theory and an experimental program including 7 full scale concrete T-beams pre-cracked in shear, reinforced with different systems, are analyzed to compare the efficiency in terms of gain of strength and feasibility of various systems developed by the industry. The different reinforcement systems analyzed are: (i) Externally Bonded (EB) system, (ii) Embedded Through Section (ETS) and (iii) Lshaped CFRP system (Sika CarboShear L). In order to compare these different building techniques, the beams used in this study are identical and all have experienced an equivalent preload causing a similar shear cracking pattern before strengthening. The experimental data collected following the static load to failure have quantified the gain offered by the different methods of reinforcement. All specimens of the study featured a shear failure except a specimen that has broken in bending and demonstrated some ductility following the strengthening. Examination of the internal deformations of the FRP reinforcement and stirrups reveals that the FRP reinforcement contributes to the resistance and helps relieve the stirrups and leads to increased shear strength. All systems have proven to be able to increase the shear strength at some degree. In assessing the various stages of preparation, by raising the design constraints and implementation and identifying the advantages and disadvantages, it is demonstrated that some systems may be better than others in some cases.

Date	3 Dec 2015
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Omar Chaallal (Supervisor) & Marie-José Nollet (Co-supervisor)