Influence of Hydrodynamic Pressure on Damping Seismic Performance of Long-span Suspension Bridge in High Intensity Seismic Region.

Strong earthquake can cause larger structural response of bridge, resulting in the interaction between structures and the surrounding water to generate hydrodynamic pressure. Taking a deep-water long-span suspension bridge in a reservoir area as the research object, longitudinal viscous dampers are set between the towers and beams for structural shock absorption, the interaction of water and the bridge tower is considered in the form of additional mass and calculated using the analytical method. By establishing four different structural system analysis models, the effects of hydrodynamic pressure on the earthquake response of long-span suspension bridge and the aseismic performance of damper are studied. The results show that the hydrodynamic pressure further enlarges the structural displacement and internal force response of the suspension bridge under the earthquake. The greater the depth of the bridge tower into the water, the more obvious of enhancement effect. The viscous damper can reduce the longitudinal displacement and structural internal force of the suspension bridge in the form of additional anti-seismic damping. However, under the influence of the seismic hydrodynamic pressure, the working hysteresis area of the damper increases, the maximum increase of damping force is 2.21%, and the maximum increase of displacement is 8.33%. Therefore, when viscous damper is adopted for deep-water bridge, the influence of seismic hydrodynamic pressure on its performance should be considered so as to avoid over-limit damage. [ABSTRACT FROM AUTHOR]