SCC Formwork Pressure: Influence of Steel Rebars

The formwork pressure exerted by a given Self Compacting Concrete (SCC) depends on its thixotropic behavior, on the casting rate and on the shape of the formwork. It can moreover be expected that, in the case of a formwork containing steel rebars, these should also play a role. In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is studied. In second part, a comparison of the theoretical predictions to the experimental measurements of the pressure drop, after the end of casting SCC, was determined and the proposed model was validated. Finally, an extrapolation is suggested of the proposed method to the case of a rectangular formwork containing a given horizontal section of steel rebars, which could allow the prediction of the formwork pressure during casting.

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