Effect of Cloisite 30B Nanoclay on Mechanical Properties, Thermal Behaviour and Microstructure of Cement Mortar

Abstract

Nanomaterials have great potential in improving properties of the cement mortar and concrete as established by various researchers. Nanomaterials can also improve the mechanical performance, volume stability, durability, and sustainability of cement mortar and concrete. In the construction industry, several types of nanoparticles have been incorporated into cement composite in which nanoclay platelets are an example of such nanoparticles that have recently been widely used in reinforcing cement matrix because of their low cost, wide availability, high aspect ratio, well developed intercalation chemistry (surface modification) and high strength and stiffness. This thesis presents an initial study on the effect of Cloisite 30B nanoclay on cement mortar. Cloisite 30B nanoclay was added in the varying proportions of 0%, 0.5%, 1%, 2%, 4% and 6% by the weight of cement. Initially the dispersion of nanoclay was carried out by aqueous mixing but due to improper dispersion, powder mixing was adopted. The cement mortar was prepared using the cement-sand ratio1:3 by weight of cement with water-binder ratio (w/b) as per the consistency of the cement. The fresh mortar paste were first cured at 100% relative humidity for 24 hours and then cured in water for 28 days. The effects of varying percentages of nanoclay in cement mortar or concrete were investigated on mechanical properties which include compressive strength, split-tensile strength and flexural strength. In addition the reaction products were characterized with XRD and TGA/DSC. SEM was employed to investigate the microstructure of final product. It was investigated that the mechanical and thermal properties of the mortar sample is improved with the addition of 2% and 4% of nanoclay but the addition of nanoclay by 6% leads to significant decrease in properties