The contribution of optical methods and geodetic instruments in Structural Monitoring: A brief historical survey

摘要

Structural Health Monitoring (SHM) is an all-embracing process of implementing a damage detection and characterization strategy for critical infrastructures. Its data acquisition portion relies on a multi-disciplinary approach that combines a variety of sensing technologies to capture, log and analyze data of various types. Engineering surveying science and practice is a key element in SHM that contributes to the detailed characterization of structures' geometry in space and time. Optical and digital imagery systems and methods form an integral part of surveying techniques, and therefore, their evolution has a profound effect in SHM applications. This paper attempts a summary classification and a critical discussion of conventional and emerging engineering surveying techniques related to optical systems for SHM. More specifically, optical sensors are categorized and cross-compared using various criteria, such as their principle of operation, their accuracy characteristics, their limitations due to atmospheric and other effects and their potential to monitor low or high dynamic phenomena. Also, practical issues of interest are examined including their ability to provide simultaneously measurements at a single- / multi- point locations and their capacity to operate remotely and /or integrated within a sensors network. Finally, examples and summary results from various sources are included to further enhance discussion.