This master’s thesis present the results of an experimental study on shear strengthening of reinforced concrete (RC) T-beams with composite materials made of fiber-reinforced polymer (FPR).
The main objective is to develop an innovative strengthening technique for RC T-beams based on the concept of closed stirrups with FRP rope passing through the flange or web. Thereby, a full wrap scheme to the reinforcement is saught. This configuration also allows for seismic shear strengthening of RC T-beams in compliance with standards that require closed stirrups to provide an adequate confinement.
The methodology includes experimental investigation and theoretical developments. The experimental program encompasses static tests on full scale RC T-beams reinforced in shear with externally bonded (EB) FRP. The scheme of the FRP anchorage system allows strapping of the beam, thereby enhancing the concrete confinement and the contribution of steel stirrups, when present. The parameters examined in this study are as follows: i) the ratio of internal steel stirrups and ii) the configuration of the anchorage system. Nine spécimens were tested to asses statically the effect of the different parameters influencing the shear behavior. The results are analysed in terms of failure mechanism, gain in shear resistance due to FRP, strain in the different components, load displacement relation and rigidity. The experimental results are compared to the requirements of standards and international design guidelines. Also, an analytical model is developed including the interaction observed between transverse steel reinforcement and the contribution to shear resistance of EB FRP. This aspect has not yet been captured up to date by the design models in current international standards and guidelines, such as CSA-S806-12, CSA-S6-14, ACI 440.2R-08 and fib TG-9.3-01.
The results of this study show that both anchorage systems substantially improve the contribution of FRP to the shear strength. They also confirm the existence of the interaction between the internal transverse steel and FRP. Finally they highlight the shortcomings of the normative models.
| Date | 11 Oct 2016 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Omar Chaallal (Supervisor) |
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Bourget, S. (Author),
Chaallal (Supervisor),
11 Oct 2016Student thesis: Master's thesis › Master in Engineering: Construction Engineering