Exploring the Sustainability of Concrete: Enhancing Durability and Eco-Strength with Micro and Nano Materials

Author(s)

Namitha Raveendran & Vasugi Krishnan

Abstract

Concrete, a cornerstone of modern construction, has long been criticised for its significant environmental impact due to high carbon emissions during cement production. However, integrating micro-materials like metakaolin (MK) and nano-silica (NS) offers a promising path toward sustainable construction. This innovative study examines the effects of MK and NS on concrete’s engineering performance, durability, and ecological footprint.

By replacing 12.50% of cement with MK and adding 2% NS, researchers achieved remarkable results, including a 30–40% increase in strength and superior durability compared to traditional concrete. The hybrid blend reduced porosity and enhanced resistance to environmental aggressors like chloride, acid, and sulphate. Additionally, MK-NS mixes showed a substantial decrease in carbon emissions, with embodied CO2 reduced from 365.87 to 341.11 kg CO2/m³.

The study highlights how MK and NS refine the microstructure of concrete by enhancing hydration and creating a denser matrix, as confirmed by advanced analyses like X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). These materials also contribute to eco-strength efficiency, improving both structural performance and sustainability by 32% over conventional concrete.

MK-NS blended concrete demonstrates immense potential for use in bridges, marine structures, and high-rise buildings, where durability and reduced environmental impact are critical. By adopting such innovations, the construction industry can balance performance demands with sustainability goals, advancing efforts to achieve Net Zero Emissions.