Global Research Trends on Rebar Coatings in Reinforced Concrete: Corrosion Resistance and Bond Behavior (2014–2024)

Corrosion of reinforcing steel significantly undermines the durability and structural integrity of reinforced concrete (RC) systems, especially in aggressive environments. Protective rebar coatings have emerged as a practical and effective solution to enhance corrosion resistance and maintain steel-concrete bond strength. This paper presents a comprehensive bibliometric and systematic review of global research trends from 2014 to 2024 on rebar coatings in RC structures. The bibliometric analysis, conducted using Scopus data and VOSviewer, highlights prolific authors, institutions, collaboration networks, and key thematic areas. Simultaneously, the systematic review critically assesses the types of coatings used including epoxy, galvanized, stainless steel, and emerging nanocomposites their mechanisms of action, and their influence on bond behavior. Results indicate a notable growth in research output, with China, the USA, and India leading global contributions. While coated rebars significantly improve corrosion resistance, their effect on bond performance varies with coating type and application method. The study identifies gaps in field validation and sustainability assessments and suggests future directions for interdisciplinary research, including AI-based modeling, life cycle analysis, and performance-based standards for coated reinforcement systems. These insights contribute to advancing durable, sustainable, and resilient infrastructure.