A survey of emerging technologies for the future of routine visual inspection of bridge structures

Bridges are important infrastructure assets that are vital for the connectivity of communities. Visual inspections remain a key method for bridge condition monitoring. However, visual inspections are often considered to be highly subjective and therefore alternative technologies are often proposed as a means of replacing or enhancing current visual inspection practices. This paper presents the results of a survey which aims to document the emerging trends for future visual inspection practice related to bridges. The implementation of new technological solutions has the potential to improve the quality of inspection data, reduce the safety risks posed to visual inspectors by moving more of the process off-site and improve the quantification of the rate of change in condition. The survey covers two key topics: (i) Emerging data capture methods and (ii) Emerging data analysis methods. Emerging data capture methods include: use of uncrewed vehicles, 360° cameras, photogrammetry, laser scanners, point cloud systems, and Interferometric Synthetic Aperture Radar (InSar). Emerging data analysis methods include: remote inspection, augmented reality and virtual reality, digital image correlation, artificial intelligence, Big Data and the Internet of Things. The survey concludes with a detailed discussion on the opportunities and barriers to implementation of the reviewed technologies and approaches.