The Effect of Varying Sand and Plastic Additives on The Mechanical Properties of Cement Matrix Tiles

Abstract

Abstract The global efforts regarding polymer waste and pollution reduction in the environment through waste recycling is essential to forestall its deleterious effect on the environment. This work focused on utilizing used plastic and sand as additive in cement matrix tile production while cement and laterite quantities were kept constant. Tile specimens having a uniform thickness of 15 ± 1 mm and facial dimensions of 150 mm x 150 mm were produced in the laboratory utilizing varying quantities of sand (30, 20, 10, 0 %) and plastic (35, 45, 55, 65 %), with constant quantities of laterite (30%) and cement (5%) additives. Laterite was thoroughly mixed with sand, plastic and cement with a known volume of water in a clean bowl. The resulting mixture was then subjected to a compaction load of 25 KN in a mould to obtain cohesive material. Two sets of samples were prepared; unfired and fired sample. The unfired sample was allowed to cure after wetting for 7 days. Thereafter, the sample to be fired was heat treated in an oven at a temperature of 2200C for 35 minutes. The fired tile specimen was removed from the oven and allowed to cool down at room temperature. The specimen was then subjected to water absorption, water shrinkage, flexural and compression tests. The results obtained showed that the tile with plastic: sand ratio of 65:0 had the best water absorption and water shrinkage values of 11.4 and 5.3 % respectively. Furthermore, the mechanical tests showed that the flexural and compression tests data of 39.08 and 158.06 MPa respectively were the best when compared to other samples for the tile with plastic: sand ratio of 65:0. It was also noted that a direct relationship existed between the quantity of plastic used and the strength of tile produced. The unfired sample could not be subjected to mechanical tests as the bonds formed between the additives were weak. It is recommended that cement quantity used be slightly increased to investigate its effect on the strength of the cement matrix tile. Based on the result, it is suggested to increase the plastic content and decrease the sand content of the sand:plastic ratio to achieve a better physico-mechanical properties of tile samples