Development of a general monitoring program for bridge stays and hangers in Wallonia

The present paper reports on the design, implementation and preliminary testing of an accurate and non-intrusive axial force monitoring system for cables with a small bending stiffness anchored to possibly flexible supports. Wireless sensors are used to measure accelerations at selected points along the cables. Vibration measurements are acquired on a daily basis and processed to get estimates of the natural frequencies of vibration of the cable that feed up a numerical algorithm for the axial force identification.