Analysis of Tower-Girder Transfer Pounding on the Yokohama-Bay Cable- Stayed Bridge during 2011 Great East Japan Earthquake

This paper presents an analysis of tower-girder transverse pounding of a cable-stayed bridge during an earthquake. The study is based on observation on pounding occurrence that involves wind-shoe, side bearing, and tower-link of the Yokohama-Bay Bridge during the March 11, 2011 earthquake. The pounding mechanism is modelled by a simplified structural model using linear contact spring to simulate the contact force between tower and girder at wind-shoe. The model is verified by comparing the simulated and identified time-history responses, spectra, natural frequencies and shapes of the transverse modes. Using the verified model, the amount of pounding force is quantified and the effect of pounding force on wind-shoe is investigated in more detailed. The study also investigates transverse pounding force effect on the structure in general for earthquakes larger than the 2011 Great-East Japan earthquake.