Ambient vibration testing of bridges by non-contact microwave interferometer

Recent progress in radar techniques and systems leaded to the development of an interferometric radar, suitable to the application in dynamic testing and vibration monitoring of civil engineering structures. The main characteristic of the new radar system is the possibility of simultaneously measuring the (static or dynamic) displacement of several points of a structure with high sensitivity. The paper describes the major characteristics of the microwave interferometer and its application to ambient vibration testing of full-scale bridges.