The construction industry is a major contributor to carbon emissions and resource depletion, which makes it essential to develop sustainable alternatives to conventional concrete. This study investigates the potential of bio-based improvements, focusing on microbial induced calcite precipitation, algae-based carbon dioxide sequestration, and biochar incorporation. Microbial induced calcite precipitation uses Sporosarcina pasteurii to form calcium carbonate within the concrete matrix, enhancing self-healing ability and structural strength. Algae-based admixtures derived from Chlorella vulgaris promote natural carbon absorption during curing and improve hydration and setting characteristics. Biochar produced from agricultural residues serves as a carbon storage additive that enhances durability, thermal performance, and water retention.
Four concrete mixes were prepared and examined for compressive and flexural strength, permeability, water absorption, and environmental performance. The experimental results showed that bio-enhanced concretes achieved superior mechanical strength and lower carbon impact compared to the control mix, with microbial concrete showing about fifteen percent higher compressive strength and biochar concrete exhibiting a twenty percent reduction in water absorption. These findings demonstrate that integrating biological and biomass-based materials into concrete production can create durable, self-improving, and environmentally responsible construction materials suitable for sustainable infrastructure.