The Effect of Exfoliated Vermiculite on the Drying Shrinkage of Cement-Sand Mortar.
This paper presents a case study of the Assessment of the effect of Exfoliated Vermiculite on the drying shrinkage of cement-sand mortar. Investigation of mortar mixes for porosity and water absorption were as well presented. One of the major factors affecting the quality of plasters is drying shrinkage which causes cracks leading to deterioration, reduced service life, aesthetic loss and increase in maintenance costs. The only solution to this problem is to incorporate admixtures in mortar at the time of construction that reduce the susceptibility of plaster to cracking. Whereas there are already existing conventional admixtures used to prevent plaster cracking, and rectify cracks after walls have been plastered, this research was aimed at using Exfoliated Vermiculite as a new admixture in plaster with less draw backs and more adhesiveness to the wall. It was so much evident through the tests that drying shrinkage of normal plaster reduced by 50% at 4% optimum of Exfoliated Vermiculite. Porosity and water absorption of mortar increased with increasing amount of Exfoliated Vermiculite with the optimum having 11.2% and 5.3% respectively. However, the tendency of Exfoliated Vermiculite to increase the water absorption rate of mortar makes its unsuitable for use on external plaster but rather on internal plaster with minimal exposure to environmental conditions of rainfall and high humidity levels.
Akello, Lydia (2023). The Effect of Exfoliated Vermiculite on the Drying Shrinkage of Cement-Sand Mortar. Kabale: Kabale Unoiversity.