Development of a statistical model of the dynamic response of a degraded cable-stayed footbridge over the Wisłok River in Rzeszów

The following paper is focused on the development of a statistical model of a cable-stayed footbridge over the Wisłok River in Rzeszów (Poland). The footbridge is highly dynamically susceptible to pedestrian traffic, and, as a preliminary test showed, the cables are strained unevenly. The numerical simulation of the footbridge is complex because the footbridge design documentation has been lost, and the technology of cable pre-tension monitoring, as well as the forces obtained in cables, after the assembly was completed, is unknown. The footbridge is a nearly 30-year-old structure, and many initial parameters, like material properties or connection stiffness, may have changed and degraded during in-service period. It would be advisable to monitor the structure's behaviour, considering the influence of various environmental conditions; however, this footbridge has not been classified as a strategic element of urban infrastructure. Due to limited financial resources, the implementation of continuous monitoring is currently not possible. As a solution to overcome the scarcity of data and funding, the App4SHM for periodical inspections of the footbridge's dynamic parameters is proposed. As a low-cost and accessible solution, the app installed in any smartphone was used for the first statistical model development based on acceleration measurements. It is expected that, based on its numerical model, a reference state condition can be established, the critical state detection for the footbridge will be possible in the future.