Utilization of Rice Husk Ash as a Replacement for Sodium Silicate in Geopolymer Concrete: A Study on Alkaline Molarity Optimization

¹ Research Scholar, Department of Civil Engineering, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Chennai, Tamil Nadu, India.
² Associate Professor, Department of Civil Engineering, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Chennai, Tamil Nadu, India.
³ Assistant Professor, Department of Civil Engineering, Sri Ranganathar Institute of Engineering and Technology, Coimbatore, Tamil Nadu, India.

Abstract

Currently considered one of the most auspicious carbon-free construction material are geopolymer binders. In addition to having minimal emissions of carbon, the manufacture of geopolymer additive materials also aids in the solution of numerous challenges related to the management of solid waste from industrial processes. Any aluminosilicate waste material can be used to create the geopolymer binder, and it is then mixed with an alkaline activator. The primary drawback of geopolymers, meanwhile, is their somewhat higher manufacturing cost when compared to traditional cement-based binders. Sodium silicate is the least environmentally friendly and most costly substance of all of them. As an economical replacement for industrial sodium silicate solution, some researchers have used a variety of silica-rich waste items, such as rice husk ash (RHA) based silicate solution. Rice husk ash (RHA), which is a residue of the Agricultural Rice production industry, was utilized as the initial source of amorphous silica to develop a solution of greener sodium silicate. This solution was then used to replace the typical commercial sodium silicate in geopolymer concrete. This paper pertains to the research conducted on the development of strength for a variety of geo-polymer concrete grades with different concentrations. To create distinct compounds, various molarities of sodium hydroxide solution (6M to 18M) are employed. The evaluation of compressive strength of the geo-polymer concrete samples is assessed at 3, 7, and 28 days of age. The GRM8 specimen proved the most promising outcomes, and as a result, RHA has the potential to be utilized as an activator for geopolymer-based concrete.