Algae-based earth materials for sustainable construction: Toward a new generation of bio-stabilized building solutions

This study explores the enhancement of Compressed Earth Blocks (CEBs) using alginate-based stabilization, promoting resource conservation and the use of renewable materials in construction. By utilizing alginates from algae— a renewable and increasingly abundant resource due to the uncontrolled proliferation of algae belts —the research addresses key limitations of traditional CEBs, such as mechanical strength and thermal efficiency. Experimental results show that alginate-stabilized CEBs achieve a compressive strength of 6.82 MPa and a 26 % reduction in thermal conductivity (from 0.69 to 0.48 W.m⁻¹.K⁻¹), enhancing insulation and energy efficiency. The stabilization mechanism involves ionic bridging, which increases porosity and performance. These findings highlight the potential of alginate-stabilized CEBs as an eco-friendly alternative to cement-based materials, contributing to sustainable construction while offering a practical application for excess algae, an environmental challenge with no current large-scale solution. This approach aligns with circular economy principles, providing a scalable, climate-resilient building strategy that reduces environmental impact and promotes innovative resource utilization.