Utilization of Waste Foundry Sand in Concrete Paver Blocks

Abstract

The need of concrete is increasing every year as the population of humans are increasing as per their demands i.e. infrastructure developments and shifting composition etc. Due to rising demands and fight to produce good quality of concrete, construction industries have overused the natural materials used in concrete, leads us to extinction in natural materials and results in rising prices of materials. Thus, the environmental problems related with excessive extraction and mining from natural sources have been reported in many countries. Due to finite availability of natural materials, and involvement of economy, it has now become very important to look as for the alternative source for natural materials used in concrete i.e. gravels and natural sand. Waste foundry sand (WFS) is a propitious material that can be used as an alternative for the natural sand i.e. (fine aggregates) in concrete. The thesis demonstrates the potential of re-use for waste foundry sand i.e. industrial by-product as a substitute of a fine aggregate in concrete. The fine aggregates i.e. (natural sand) are replaced with WFS in six different substitution rates i.e. (2.5%, 5%, 7.5%, 10%, 12.5% and 15%). Several tests were performed to examine the mechanical properties i.e. (compressive strength, flexural strength and splitting tensile strength) as well as the durability of concrete i.e. (sulphate resistance). The results indicate that the compressive strength was increased from 3.93%–9.3%, splitting tensile strength increased from 4.8%-11.37%, flexural strength increased from 3.81% -12.27% for 2.5%-5% replacement levels of waste foundry sand with fine aggregates in concrete and after that there is a systematic decrement in strength as the percentage goes on increasing at curing age of 28 days. The strength in Sulphate resistance test was increased up to percentage level of 10% with natural sand as a fine aggregate in concrete and after that there is a systematic decrement in strength. From following results, it was concluded that 10% WFS replacement level of WFS with fine aggregate in concrete can be effectively used to make concrete and various application of concrete i.e. (concrete paver blocks) and beyond 10% WFS replacement level is not beneficial.