The Use of GPS for Disaster Monitoring of Suspension Bridges

The use of kinematic GPS for deformation monitoring and now deflection monitoring of structures is an ongoing topic of research. It is now possible to measure the 3D deflections of discrete points upon a structure at a rate of up to 100Hz with GPS alone. The precisions of these results are typically sub centimetre, and real time is possible. However, with the integration of GPS with other sensors such as accelerometers the data acquisition rate can be increased up to 2,000Hz or so. The GPS based deflection measurements have the distinct advantage over other sensors in that GPS doesn’t drift, uses precise time and can be used in all weather.

The following paper discusses some of the background to this work as well as showing three case studies whereby GPS has been used on bridges to measure the deflection and natural frequencies of the bridges. The bridges investigated are the Nottingham Wilford Suspension Bridge, The London Millennium Bridge and the Humber Bridge.

The paper also uses this and previous knowledge to discuss the possible use of such a GNSS based deflection monitoring strategy and combining this with Finite Element Modelling of such a structure to allow a disaster monitoring tool to be developed.