In the quest to reduce the construction industry’s environmental footprint, researchers are turning to innovative materials that can replace traditional cement. A recent study published in *Jurnal Ilmiah SINERGI* (which translates to *Journal of Synergy*) explores the potential of rice husk ash-based geopolymer mortar as a sustainable alternative for patch repair in concrete structures. This research, led by Pinta Astuti from the Department of Civil Engineering at Universitas Muhammadiyah Yogyakarta, offers promising insights into the mechanical properties and microstructural characteristics of this eco-friendly material.
The construction sector’s rapid expansion has led to a significant increase in cement use, contributing to substantial CO2 emissions. Geopolymers, which are eco-friendly construction materials, have emerged as a viable solution to reduce cement consumption. Among these, rice husk ash, a pozzolanic material rich in aluminosilicate, is abundant and suitable for geopolymer binders. Astuti’s research delves into the use of rice husk ash and alkali activators (NaOH/Na2SiO3) with varying activator percentages (40%, 45%, and 50%) to evaluate their mechanical properties and potential applications as patch repair materials.
The study involved formulating an optimal mix design through trial and error in a laboratory setting, followed by curing at 70 °C and testing at room temperature. XRF and SEM-EXD analyses were performed to determine the chemical composition and microstructure of the specimens. The activators, NaOH and Na2SiO3, were employed in a 1:3.5 ratio, with 14M molarity and 2% superplasticizer, to enhance workability.
The results were promising. The geopolymer mortar achieved its highest compressive strength of 8.14 MPa at a 40% activator variation. The highest split tensile and flexural strengths were 2.50 MPa and 1.00 MPa, respectively, both at a 50% variation. These findings demonstrate the suitability of the mortar for patch repair on concrete substrates with compressive strengths below 8 MPa.
“The mechanical properties of the rice husk ash geopolymer mortar were influenced by the silica, calcium, and alkali activator content, affecting the mortar’s strength and density,” Astuti explained. This research highlights the potential of rice husk ash-based geopolymer mortar as a sustainable and effective patch repair material, offering a greener alternative to traditional cement-based solutions.
The implications for the energy sector are significant. As the demand for sustainable construction materials grows, the development of eco-friendly alternatives like rice husk ash-based geopolymer mortar could reduce the environmental impact of construction projects. This innovation not only addresses the need for durable and efficient repair materials but also contributes to the broader goal of reducing carbon emissions in the construction industry.
Astuti’s research, published in *Jurnal Ilmiah SINERGI*, underscores the importance of continued exploration into sustainable construction materials. As the industry moves towards greener practices, the adoption of geopolymer mortars could pave the way for a more environmentally conscious future. This study not only provides valuable insights into the mechanical properties and microstructural characteristics of rice husk ash-based geopolymer mortar but also sets the stage for further research and development in this promising field.