Title: Influence of Polyol on the Drying and Curling of Self-Leveling Screeds Based on Calcium Sulfoaluminate Cement

Author(s): J. Ambroise, J.-F. Georgin, and J. Pera

Publication: Symposium Paper

Volume: 234

Issue:

Appears on pages(s): 445-456

Keywords: calcium sulfoaluminate cement; curling; drying shrinkage; mass loss; polyol; porosity

DOI: 10.14359/15951

Date: 3/22/2006

Abstract:
The development of cement-based screeds unbound to their support is still limited because of the curling which occurs at the corners and perimeter of the screed. This phenomenon is mainly due to the moisture gradient that appears within the thickness of the screed: the upper surface dries and shrinks, while the lower one remains humid. One possible solution limiting this phenomenon is using calcium sulfoaluminate cement instead of normal portland cement. Experiments utilizing an original device show that the curling is three times lower when using calcium sulfoaluminate cement. Moreover, when polyol is added to the mixture (0.63% of the cementitious material content), curling is still reduced by 23%. Polyol reduces drying shrinkage by 40%, but does not affect the mass loss of the screed and the porous distribution. The results obtained show that polyol can be considered as an efficient shrinkage reducing admixture (SRA) for calcium sulfoaluminate-based mortar and concrete.