Under earthquake loading, rational structural failure patterns are the basis for ensuring structures to survive. However, the studies on seismic failure patterns and their control were rarely reported in literatures especially for long span cable-supported bridges. In this paper, elasto-plastic analyses were carried out to investigate seismic damage and failure patterns by employing seismic damage indices for a trial designed cable-stayed bridge, which has a central span of 1400 m and is excited by various ground motion intensities. Damage control strategies were presented, by installing viscous dampers between the pylons and the girder as well as between the piers and the girder, which are expected to reduce the damage of structure and improve the capacity of collapse resistant. The influence of the damper allocations and coefficients on structural damage and failure pattern were studied under extremely ground motion (Peak Ground Motion Acceleration (PGA) =1.0g) in transverse direction of bridge. In addition, the influence of the stiffness of the supporting piers on structural seismic performance was also investigated. The effects of stiffness and energy dissipation capacity of the cross beam of the pylon were further discussed. Moreover, damage control counter measure installing energy dissipation components between the pylon legs was presented. The results show that the pylon top and bottom regions are simultaneously subjected to damage under extremely earthquake, indicating a failure pattern of double plastic hinges; the damage control strategies with additional dampers can effectively reduce the damage of piers, however, it is not effective enough to the damage of towers; the energy dissipation components installed between the pylon legs at the top region can improve the failure pattern of the pylon and the damage control targets based on seismic damage indices can be satisfied.