Advances in GPS and GNSS Over the past 44 years, and its application to measure the movements of long bridges

Description

The talk will show how the GNSS systems have evolved over the years, allowing civilian users to obtain better quality measurements, improved availability and interoperability between numerous GNSS.
The talk will also discuss the use of GNSS to measure the movements of long bridges. Such structures can be 1 or 2km in length and are designed to be flexible and move backwards and forwards. Gethin first attached a GPS antenna to the Humber Bridge in the UK in 1995. Since then, he has carried out work on 7 long span bridges. Today, GNSS technologies are used as standard on large bridges in Asia as part of their structural health monitoring.
The talk will focus on how GNSS technologies can be used to monitor both the magnitude of the movements in 3D, as well as the frequencies of such movements. Through measuring GNSS data at rates of 20Hz or more, higher frequencies are obtained, using On The Fly ambiguity resolution to result in millimetre level precisions, and usually in real time. Such movements are caused by several influences on the structures, such as traffic loading, wind loading, temperature variations, as well as damage and corrosion.

Period	24 Nov 2022
Event title	Geospatial Centre of the Faroe Islands; Technical Seminars: Monthly technical talks
Event type	Seminar
Degree of Recognition	National