Low-carbon materials in construction: opportunities and challenges for civil engineers

Abstract

The construction industry significantly contributes to global carbon emissions, necessitating the exploration of low-carbon materials as sustainable alternatives to conventional materials like Portland cement concrete. This study evaluates the performance, challenges, and opportunities of adopting low-carbon construction materials such as geopolymer concrete, alkali-activated binders, bio-based composites, and recycled aggregates. The primary objectives were to assess their mechanical strength, thermal performance, and embodied carbon, identify adoption barriers, and propose practical strategies for their integration into construction practices. Experimental methods included compressive strength testing, thermal resistance measurement, and life cycle assessment (LCA) for embodied carbon quantification. Statistical tools, such as one-way ANOVA and regression analysis, were applied to validate the findings and identify correlations between environmental and performance metrics.Results indicated that geopolymer concrete exhibits superior compressive strength (55 MPa) and a 50% reduction in embodied carbon compared to conventional concrete, making it ideal for structural applications. Bio-based composites demonstrated excellent thermal insulation properties (R-value: 2.5 m²•K/W) but were limited to non-load-bearing applications due to their lower mechanical strength. Recycled aggregates retained approximately 85% of the compressive strength of conventional aggregates while significantly reducing embodied carbon. Economic challenges, lack of standardized testing protocols, and technical uncertainties were identified as key barriers to adoption.The study concludes that low-carbon materials offer significant potential to reduce the construction sector's environmental footprint while maintaining performance. Practical recommendations include cost-reduction strategies, hybrid material development, policy-level interventions, and workforce training to promote their widespread adoption. Future research should focus on optimizing material properties, improving durability under extreme conditions, and integrating digital technologies like Building Information Modeling (BIM) to enhance efficiency and sustainability in construction.