Dynamic Sensitivity of Footbridges: Modal Identification, Human-Induced Vibrations, and Emerging Solutions for Sustainable Design

Lightweight and slender footbridges exemplify sustainable, material-efficient infrastructure, yet their vibration performance is frequently governed by high dynamic sensitivity, which directly affects serviceability, user comfort, and structural durability. This paper provides a critical review of full-scale experimental investigations and validated finite element simulations addressing the dynamic behavior of various footbridges, focusing on the influence of structural typology, material solutions, and excitation characteristics on vibration-related performance within sustainability-driven design objectives. This article is organized into three core research themes: (1) standards and guidelines in bridge engineering practice, (2) dynamics of footbridges with special structural response to human-induced loading, including walking, running, crowd actions, and higher harmonic contributions, and (3) case studies, based on which the gaps in the current approach are formulated. Based on a synthesis of findings from leading research on structural dynamics and sustainable infrastructure, this paper highlights critical gaps in current vibration serviceability guidance for footbridges. Concluding remarks delineate the principal research challenges and formulate evidence-based, practical recommendations to enhance the resilience, vibration comfort compliance, and sustainability of future footbridge infrastructure.