Sensor-Based Structural Assessment of Aging Bridges

Transport infrastructure managers need to ensure longevity of their networks to meet pressing sustainability demands. Extending the operational life of complex structural systems, such as aging bridges, requires a comprehensive life-expectancy assessment. Given that these structures are suffering from local failures that may not necessarily alter their global response, engineers need to increase their confidence in detecting and characterizing such damage, while assessing deterioration rates in localized regions. This chapter presents data analysis results from the structural health monitoring of three aging bridges: two masonry arch rail bridges, and a half-joint concrete motorway bridge. The aim, in all cases, is to improve deterioration assessment through enhanced sensing of the distributed response across the structures. A core sensing technology used in the three schemes is the development of fiber Bragg grating (FBG) networks, allowing the study of small dynamic strain variations at both the local and global response levels. New ways of installing FBGs are explored for multi-aspect condition monitoring, while their sensitivity in damage detection is enhanced with data analytics and acoustic emission (AE) sensors. The chapter discusses that complementing information from dynamic strain and AE-sensing networks may enable a finer deterioration monitoring of aging structures driven by data.