The Effect of Date Syrup-based Graphene Coated Sand on the Mechanical Properties of Cement Composites

Abstract

Numerous studies have previously investigated the effect of including nanomaterials into cementitious mixtures in an attempt to mitigate some performance drawbacks associated with it. Recently, research has been going to investigate the influence of graphene, owing to the many superior intrinsic properties distinguishing this material, such as its high strength, large specific surface area, and high aspect ratio, all of which are believed to promote the nucleation effect and refine the products of the hydration process to produce stronger and more durable cement composites. In literature, graphene had been mainly incorporated either in the form of graphene oxide sheets or as graphene nanoplatelets, the degree to which graphene reinforcement can improve the performance is largely dependent on how uniformly graphene sheets can be distributed in the matrix and the surface chemistry of the particular form. In this study, graphene is incorporated into the cement matrix in the form of graphene coated sand prepared by graphitization of date syrup coating desert sand particles through pyrolysis. The mechanical performance of cement paste and mortar upon the addition of varying dosages of date syrup-based graphene sand hybrid (D-GSH) was investigated experimentally at different curing ages. For cement paste, the maximum increase in the 28 days compressive strength and modulus of elasticity were 12.43 % and 12.46 %, respectively, for 0.1 % D-GSH addition, similarly for mortar, the enhancement was 38.46 % and 28.46 % for 0.5 % D-GSH/sand replacement. As for the 28 days flexural strength of mortar, the maximum enhancement was 12.18 % for 0.5 % D-GSH/sand replacement. Moreover, a comparison between the influence of implementing three different mixing methods on the compressive strength of mortar samples having a fixed D-GSH addition was performed to determine the optimal sequence of mixing materials with graphene inclusion. Finally, the flow table test was conducted to evaluate the effect of D-GSH on the consistency and flowability of mortar. Mortar mixtures became denser and less flowable with the increased addition of D-GSH.

Date of Award	6 Dec 2023
Original language	American English
Supervisor	Tae Yeon Kim (Supervisor)