Effect and mechanism of controlled permeable formwork on concrete water adsorption

Controlled permeability formwork (CPF) is a kind of non-woven formwork, which is a widely used product in the spinning industry. In this paper, the effect of CPF on the water adsorption property of concrete was studied. Surface appearance, meso-surface morphology and microstructures of concrete blocks were characterized to analyze the affecting mechanism of CPF on concrete adsorption. It was found that, by applying CPF, concrete permeability was markedly reduced due to the improved surface and microstructures. In addition, the surface structure of the CPF liner was studied by SEM. It was indicated that the CPF was a beneficial and promising material for the improvement of concrete performances.

► Casted with CPF liner, concrete permeability could be markedly reduced.
► Visible surface appearance, meso-surface morphology were improved which was verified by SEM.
► Porosity of the surface slices of samples casted with CPF liner was much lower than that of control.
► Structures of the current CPF liner was not perfectly uniform.