A review on self-sensing fiber-reinforced polymer composites : mechanisms, fabrications, and applications

Abstract

Self-sensing fiber-reinforced polymer (SSFRP) composites have attracted significant attention for their dual functionality, providing mechanical reinforcement while autonomously detecting and quantifying mechanical strain and external loads for real-time structural health monitoring (SHM). This review explores the multifaceted sensing mechanisms of SSFRP composites, including piezoresistive, piezoelectric, capacitive, optical, triboluminescent, and magnetic principles, for the detection and quantification of mechanical strain. This review compares sensing characteristics, limitations, and application suitability of these sensing mechanisms, highlighting hybrid and multi-modal sensing, as an effective strategy to strike a balance among spatial coverage, frequency bandwidth, durability, and integration complexity in SSFRP-based SHM. We critically analyze fabrication techniques categorized into two approaches: (i) integrating sensing materials through functionalized fibers or matrices, and (ii) directly embedding sensing elements via traditional manufacturing or additive manufacturing, which enables precise customization of composite architectures. Furthermore, the applications of SSFRP composites are discussed with a focus on process monitoring during fabrication and SHM in operational environments. By synthesizing recent advances and challenges, this review provides a foundational framework to guide the development of next-generation SSFRP composites for aerospace, civil infrastructure, and smart robotics.