Preliminary investigation and life cycle assessment of artificial reefs with recycled brick-concrete aggregates

An economical and environment-friendly artificial reef concrete using fully recycled brick-concrete aggregate as raw material was proposed. This study investigates the mechanical properties, drying shrinkage, chloride ion penetration, and biological adaptability of the reef. A comparative analysis is conducted on the environmental impacts (EI), carbon emission impact and cost efficiency of artificial reefs, considering natural aggregate concrete and recycled brick-concrete aggregate concrete at the material level. The results indicate that the use of recycled brick-concrete aggregates can achieve service performance equivalent to that of natural aggregates. Field investigations involving samples immersed in seawater for six months reveal the positive trapping effects of recycled materials on aquatic organisms. The Life Cycle Assessment (LCA) results reveal that achieving a 100 % replacement rate of recycled brick concrete aggregate (RBCA) creates a positive feedback loop for carbon emissions when appropriately incorporating industrial waste materials like fly ash and silica fume. In comparison to ordinary concrete, the utilization of recycled materials can significantly reduce construction costs, up to 63.7 %, thereby presenting notable economic advantages. •Introduces cost-effective, eco-friendly artificial reef concrete using fully RBCA.•RBCA performs comparably to natural aggregates.•Recycled brick aggregate enhances artificial reef biological adaptability.•Establishes a comprehensive LCA evaluation model.•Emphasizes economic advantages of proposed artificial reef concrete.