Mutualism of barnacles and marine concrete: a review of interactions, challenges, and opportunities toward eco-friendly coastal infrastructure

Marine concrete is vital for coastal infrastructure but faces significant challenges from barnacle colonization, which both compromises marine concrete integrity and offers protective benefits, necessitating a deeper understanding of the mutualistic interactions between barnacles and marine concrete. This review addresses the critical question of how to harness the positive effects of barnacles while mitigating their negative impacts on marine concrete durability and performance. It examines barnacle biology, attachment mechanisms, and their dual effects on concrete, alongside innovative strategies in material and structure design, monitoring, maintenance, and rehabilitation. Key findings reveal that while barnacles protect concrete from abrasion and chemical degradation, their colonization increases the risk of microcracking, surface defects, and hydrodynamic drag, highlighting the need for balanced, interdisciplinary solutions. By integrating sustainable materials, bio-inspired strategies, and artificial intelligence innovations, this review provides a pathway for developing resilient, eco-friendly marine concrete structures that support both structural longevity and marine ecosystem health.