Experimental and Analytical Investigation of Carbon Footprint and Material Characterization of Normal to High-Strength Concrete Incorporating Alternative Binders and Multiple Cement Sources

Abstract

Concrete, the most widely consumed construction material after water [Ref], is also a major emitter of carbon dioxide due to its reliance on ordinary Portland cement (OPC). The production of one tonne of cement typically releases about 0.8 tonnes of CO₂ [Ref], making clinker reduction a central challenge in sustainable construction. This review synthesizes experimental and environmental studies on normal- to high-strength concretes (NSC and HSC) prepared with alternative binders and diverse cement sources. Supplementary cementitious materials (SCMs)—including metakaolin, silica fume, and alccofine—are evaluated alongside bio-waste options such as seashell powder and microbial binders. Life Cycle Assessment (LCA) outcomes are integrated to quantify carbon footprint reductions at both material and structural scales. While HSC exhibits higher per-unit emissions, its superior efficiency in tall structures often leads to net savings in embodied carbon. Hybrid binder systems demonstrate synergistic benefits in strength, durability, and eco-efficiency. Remaining research challenges include insufficient long-term durability evidence, inconsistent LCA reporting, and the lack of standardized mix design protocols for multi-source concretes. Addressing these gaps through coordinated experiments, field-scale validation, and digital optimization is vital for advancing low-carbon concretes from laboratory studies to practical applications.