Methods for fast and reliable determination of damping and tension force of stay cables

After the construction of cable-stayed bridges it is always necessary in the framework of bridge inspections and special investigations to determine the static and dynamic parameters like cable force and the damping of the stay cable. Methods employed so far have often been too cost-intensive and time-consuming whereas the results have indicated in terms of the cable force deviations of up to +/- 10%, which often proved to be insufficient for engineers and operators. In the framework of several research projects measurement and evaluation methods have been developed for both parameters and which can be applied faster and easier and at the same time improve the accuracy of the cable force determination to +/- 1%. As concerns the damping parameter, an evaluation method has been developed which satisfies the constructive requirements and leads to reliable and reproducible damping values.