Advances and Challenges in Concrete Repair Materials: A Review

Abstract

Concrete, as the most widely used construction material globally, is inevitably subject to various types of damage and deterioration during its long service life. Effective and durable repair is crucial for ensuring the safety of concrete structures and extending their service life, with the performance of the repair material directly determining the repair outcome. This paper provides a systematic review of the current state of research on concrete repair materials. It begins by explaining common concrete pathologies and the performance requirements for repair materials. Subsequently, it focuses on reviewing the composition, mechanisms, characteristics, and research progress of main types of repair materials, including cement-based repair materials, polymer-modified cementitious materials, polymer repair materials, geopolymer-based repair materials, and novel smart repair materials (such as self-healing concrete). By comparing and analyzing key performance indicators like compressive strength, bond strength, durability, and shrinkage, the advantages, disadvantages, and suitable applications of these materials are revealed. The core evaluation system of repair material compatibility (mechanical, physical, chemical) is also summarized. Finally, addressing current research challenges, future directions are outlined, including trends towards green/low-carbon solutions, functional intelligence, long-term durability, and the advancement of digital design and construction technologies.