Radar-based measurement of deflections on bridges and large structures

Recent progresses in radar techniques and systems have favoured the development of microwave interferometers, suitable to the non-contact measurement of deflections on large structures. The main characteristic of the new radar systems is the possibility of simultaneously measuring the static or dynamic deflection of several points on a large structure with high accuracy. The objectives of the paper are: a) to discuss some radar techniques implemented in the microwave interferometer, in order to highlight advantages and potential issues of the radar-based measurement; b) to illustrate the application of the radar technique in live-load static and ambient vibration tests performed on a full-scale bridge.