SHM-informed Management of Long-span Bridges: Motivation, Approach and Challenges

Structural Health Monitoring Systems (SHMS) are increasingly present in most modern long-span bridges. Those systems can be used to better assess the performance of structures by reducing the uncertainties associated with deterioration modelling. This can potentially lead to a reduction of the operational costs. Despite their promise and potential, a gap still remains between the outcomes of those systems and practical bridge management decisions. As a result, huge amounts of data can be continuously collected which are not readily useable, thus being of reduced interest in practical terms. Methodologies which integrate SHMS within Bridge Management Systems (BMS), need to be developed to address asset management issues traditionally informed by visual inspections and scarce Non Destructive Tests (NDT). This integration should overcome the shortcomings of current approaches and exploit the advantages offered by modern sensor technologies.
The present paper reviews the different uses of SHMS on long-span bridges. The motivation of using SHMS to inform and improve bridge management decisions is presented. The interest of a local monitoring approach targeting selected structural components is highlighted. The need of a combined approach between traditional inspection techniques, NDT and monitoring is justified in
terms of spatial and temporal coverage. The relevance of probabilistic approaches to assess and update structural performance indicators is outlined. The case of the Great Belt Bridge (Denmark) is described to illustrate the use of SHMS on long-span bridges, together with an overview of ongoing research.