Performance evaluation of sodium silicate waste as a replacement for conventional sand in geopolymer concrete

Abstract

Excessive exploitation and increased demand for conventional sand made an unbalanced ecosystem; a suitable and sustainable alternative has to be adopted to preserve the ecosystem. The present investigation examines the performance of Sodium Silicate Waste (SSW), an industrial by-product of 100% sand replacement in geopolymer concrete (GPC). The investigation's significance lies in employing industrial waste SSW as an alternative for regular mining sand. The densities of all GPC mixes fall between 2136.7 kg/m3 and 1750.28 kg/m3. Following EN 206-1, the SSW blended GPC can be termed as lightweight concrete, which falls under energy-efficient and sustainable construction practices. The test results show that the percentage increase in industrial waste SSW from 25% to 100% improves the Compressive Strength (CS) to peak at 45.01 MPa. Comparative analysis between River Sand (RS) and SSW mixes shows that SSW blended GPC mixes produced higher strength with the increasing SSW content than GPC mixes with RS. From the Eco-efficient performances, it is concluded that replacing RS with SSW with 25%–100% may lead to sustainable GPC production in terms of cost, carbon, and energy efficiencies.