Abstract

The rapid growth of the world's construction industry is profoundly affecting the cost of construction materials, as well as the natural resources required to produce the materials and environment. Besides, waste plastic bottles are also becoming another challenge in our surroundings due to their presence in large amounts and their nonbiodegradability property. Even if various methods were attempted to manage this waste, applying it as the partial replacement for different construction materials seems feasible concerning solving the above-stated problems. The objective of this research was to investigate the competency of waste plastic bottles as partial replacement of sand in a cement tile production through conducting workability, dry density, water absorption, and compressive strength test on it at the particular 7th and 21st days of curing. Experimental laboratory method used in this research design for testing some physical and mechanical properties of cement tiles. Other than this comparative method was also applied to compare different properties of controlled cement tile with cement tile made with just 3%-33% ground waste plastic bottle as sand at 3% incremental ratio and also cement tile produced by sodium hypochlorite treated plastic sand. The result showed an increment in the workability of the fresh concrete of the cement tile, decrement in compressive strength, reduction in dry density, and declined water absorption result. Finally, the study concluded the possibility of partial plastic replacement of sand in a cement tile production up to 32.11% replacement ratio for 21st day curing ages and even if the replacement above 32.11% had an adverse effect on the compressive strength and workability of cement tile, it also got an advantage with respect to dry density and water absorption. Also, the study revealed the power of sodium hypochlorite solution in improving the high physical and mechanical properties of cement tile. It recommended for the responsible parties to apply this technology in the real production process of cement tile.

Abstract

Cement is one of the components of concrete plays a great role in the construction industry. Nevertheless, it is the most expensive and environmentally unfriendly material. Therefore, requirements for economical and more environmentally-friendly cementing materials have extended interest in other cementing materials that can be used as partial replacement of the ordinary Portland cement. This research was, conducted to examine the suitability of calcined termite hill clay powder as a cement replacing material in the production of C-25 grade concrete as a relief for this problem. The Termite Hill Clay sample was collected from Bokuluboma vicinity. The sample was calcined at the temperature of 650°C using muffle furnace, ground to the fineness of 150 µm and its chemical composition was investigated. Normal consistency and setting time of the paste having Ordinary Portland Cement and calcined termite hill clay powder from 0% to 40% replacement in 5% increment percentage investigated. The compressive strength of eight different concrete mixes with the CTHCP replacing the ordinary Portland cement prepared for 22MPa and 34MPa (i.e., for 7th and 28th days targeted compressive strength) concrete with water cement ratio of 0.5 and 360kg/m3 cement content. The properties of the mixture assessed both at the fresh and hardened state. Results revealed that calcined termite hill clay powder found pozzolanic and can partially replace cement. It has shown that up to 11.3% replacement of the ordinary Portland cement by CTHCP, the cubes achieved a target mean compressive strength of C-25 grade concrete at 28th day 34Mpa. Although, the replacement percentage greater than 11.3% of the cement of calcined termite hill clay powder in the concrete has shown a slightly lower compressive strength. Moreover, the mix indicated workable up to 25% replacement percentage and also the setting time of the paste containing calcined termite hill clay powder found faster than that of the control mix. Hence, it is concluded that CTHCP was suitable to replace cement partially with 11.3% replacement of cement by calcined termite hill clay powder as the optimal percentage of the production of C-25 grade concrete. The fresh concrete mix was workable up to 25% replacement, and the mineral admixture served as an accelerator which is suitable for cold weather concreting works.

Abstract