Journal of the South African Institution of Civil Engineering
On-line version ISSN 2309-8775
Print version ISSN 1021-2019
BOUHAROUN, S. Friction behaviour of fresh concrete in the vicinity of formwork. J. S. Afr. Inst. Civ. Eng. [online]. 2013, vol.55, n.3, pp.10-17. ISSN 2309-8775.
This study seeks to understand the mechanisms that occur at the concrete/formwork interface when fresh concrete is poured into the formwork. Four ordinary concretes with paste volumes of 28, 30, 32 and 34%, and four concretes at different dosages of superplasticiser were studied. The rheological properties of fresh concrete were measured using the ICAR rheometer. A detailed study of the friction at the concrete/formwork interfaces was then performed using a plane/plane tribometer. The results highlight the role of the volume of paste and the superplasticiser dosage on the tribological behaviour of fresh concrete. The evolution of friction stress is linear (Coulomb's Law) regardless of the formulations tested in this study. In addition, these friction stresses at the concrete/formwork interface depend on the paste volume and the dosage of superplasticiser in the concrete.
Keywords : rheology; tribology; concrete formwork; friction stress; concrete formulation.