Using Multi-constellation GNSS and EGNOS for Bridge Deformation Monitoring

Bridges are important transport nodes and play a vital role in socio-economic development across Europe and worldwide. The investments for constructing major bridges are enormous and the associated inspection and maintenance costs can also be very significant. Bridges must survive the attacks of high speed wind loading, earthquakes and current scouring. Aging, and increasing traffic volume and single vehicular weight are other factors affecting bridge serviceability. The University of Nottingham in the UK is one of the world leading institutions that initiated GPS-centred bridge monitoring in the mid 1990s. The first part of this paper is an overview to the past research and development that were carried out by the University of Nottingham on almost all the major bridges in the UK such as the Humber Bridge, the Forth Road Bridge and London Millennium Bridge. Through extensive simulation, the authors introduce achievable positioning performance using GPS and Galileo systems. A latest Structural Health Monitoring System (SHMS) that is based on real-time high-precision GNSS positioning that could take the maximum benefits offered by the European Geostationary Navigation Overlay Service (EGNOS) and the EGNOS Data Access Service (EDAS) is also presented. The final part of this paper covers the deformation monitoring results based on the network RTK GNSS positioning that is integrated with precisely synchronised tri-axial accelerometer to enhance the positioning accuracy, quality (integrity), availability, and robustness of the proposed monitoring system. It is concluded that millimetre 3D positioning accuracy could be achieved using the system proposed in this paper.