ABSTRACT
Recent advances in radar techniques and systems have favored the development of microwave interferometers, which are suitable for the non-contact measurement of deflections on large structures. The main characteristic of the new radar systems, entirely designed and developed by Italian researchers, is the possibility of simultaneously measuring the deflection of several points on a large structure with high accuracy, in static or dynamic conditions. In this chapter, the main radar techniques adopted in microwave remote sensing are described, and advantages and potential issues of these techniques are addressed and discussed. Subsequently, the application of microwave remote sensing in live load static and ambient vibration tests performed on full-scale bridges is presented in order to demonstrate the reliability and accuracy of the measurement technique. Furthermore, the simplicity of use of the radar technology is exemplified in practical cases, where the access with conventional techniques is uneasy or even hazardous, such as the stay cables of cable-stayed bridges.
