Cable-stayed Bridge Resonance with Cables: Dubrovnik Bridge Case Study

After opening of Dubrovnik cable – stayed bridge violent vibrations of bridge deck and pylon in strong Bora wind were observed, caused by violent vibrations of bridge cables. This paper analysed this phenomenon, i. e. causes for violent vibrations of cables and its impact on the overall dynamic behaviour of the bridge. It has been shown that models substituting the behaviour of massive bridge cable and its impact on the dynamic properties of the overall cable - stayed bridge can be implemented. In this analysis the following has been concluded: The response of cable - stayed bridge systems to a general type of external dynamic loading could be disturbed by the vibration of cables, especially when the eigenfrequencies of the bridge structure approach the vicinity of the eigenfrequency of any of the cable - stayed bridge cable. In this case cable's stiffness will be suddenly reduced and it starts vibrating in large amplitudes. At the end the measures for the bridge rehabilitation are presented in a way of suppressing of cable's vibrations by dampers of Maurer type.