ABSTRACT

Under near-field ground motions, fluid viscous dampers (FVDs) are effective in controlling deck longitudinal displacement but lead to the increase of bending moment and shear force at tower base. Negative stiffness (NS) devices are introduced in combination of FVDs for the bridge. The NS devices lengthen the fundamental vibration period of the bridge to reduce the spectrum acceleration whereas FVDs introduce extra damping to the bridge system to reduce the deck displacement. After implementing NS devices, designers have more options of designing FVDs for seismic control of the cable-stayed bridges while maintaining the design requirements under near-field seismic excitations.

摘要

在近场地面运动下，流体粘性阻尼器（FVD）在控制甲板纵向位移方面是有效的，但会导致塔基处弯矩和剪力的增加。负刚度 (NS) 装置与桥梁的 FVD 相结合。NS 装置延长桥梁的基本振动周期以降低频谱加速度，而 FVD 为桥梁系统引入额外的阻尼以减少桥面位移。实施 NS 设备后，设计人员在设计用于斜拉桥地震控制的 FVD 时有更多选择，同时在近场地震激发下保持设计要求。