• VISHAL CHAUDHARI
• RAJAN KUMAR SINGH

The increasing environmental concerns associated with Portland cement production have accelerated the search for sustainable, carbon-negative alternatives in the construction sector. Geopolymer concrete (GPC), synthesized using industrial by-products, offers a viable pathway toward reducing CO₂ emissions while maintaining superior performance characteristics. This study focuses on evaluating the mechanical, durability, and carbon-negative properties of geopolymer concrete incorporating industrial slag and biochar as supplementary binder materials. Ground granulated blast furnace slag (GGBS) was employed as the primary aluminosilicate precursor, while biochar derived from biomass waste was introduced in varying dosages 0%, 1%, 2%, 3%, 4% and 5% by weight of binder. The influence of biochar content on the compressive strength and split tensile strength of the developed GPC mixes was systematically examined. Durability properties, including water absorption, sorptivity, and acid resistance, were also evaluated to assess the long-term performance. Results indicated that the incorporation of biochar up to an optimum level of 2–3% enhanced both compressive strength and split tensile strength, attributed to improved microstructural packing, internal curing, and better geopolymeric gel formation. Beyond the optimum dosage, a marginal strength reduction was observed due to increased porosity. The inclusion of biochar also improved resistance to water ingress and acid attack, confirming enhanced durability. Furthermore, carbon balance analysis revealed a significant reduction in the embodied carbon footprint, demonstrating the carbon-negative potential of the developed slag biochar geopolymer concrete. Overall, this research establishes that the synergistic use of industrial slag and biochar not only enhances the mechanical and durability properties of geopolymer concrete but also contributes to carbon sequestration, promoting sustainable and eco-efficient construction practices.

Geopolymer concrete, Industrial slag, Biochar, Compressive strength, Split tensile strength and Carbon-negative concrete

"Evaluation of Mechanical, Durability, and Carbon-Negative Properties of Geopolymer Concrete Incorporating Industrial Slag and Biochar ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 12, page no.b60-b66, December-2025, Available :http://www.jetir.org/papers/JETIR2512109.pdf

"Evaluation of Mechanical, Durability, and Carbon-Negative Properties of Geopolymer Concrete Incorporating Industrial Slag and Biochar ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 12, page no. ppb60-b66, December-2025, Available at : http://www.jetir.org/papers/JETIR2512109.pdf