基于负刚度装置的超长联大跨连续梁桥地震反应控制研究

Seismic response control of long-span and super-long unit continuous girder bridges based on negative stiffness device

为完善超长联大跨连续梁桥的减、隔震技术,将负刚度装置引入到超长联大跨隔震连续梁桥中组成新型减、隔震系统,并与黏滞阻尼器-摩擦摆支座组合减震系统进行比较。基于CSiBridge软件建立全桥有限元模型,负刚度装置采用弹性多段线模拟,摩擦摆支座采用双线性恢复力模型,黏滞阻尼器采用Maxwell模型,输入3条地震波进行非线性时程分析,考查两种新型减、隔震系统下桥梁结构的地震反应,探究负刚度系统及黏滞阻尼器系统对超长联大跨连续梁桥地震反应的控制效果。研究结果表明:负刚度装置与黏滞阻尼器均可以有效地减小超长联大跨隔震连续梁桥的支座位移。负刚度装置对桥墩内力反应及梁体加速度反应的控制优于黏滞阻尼器。负刚度装置在超长联大跨连续梁桥地震反应控制中有较好的应用前景。

To improve the seismic isolation technology of long-span and super-long-unit continuous girder bridges,we proposed a novel seismic isolation system by introducing a negative stiffness device(NSD)into the bridge and compared it with the combined isolation system of viscous dampers and friction pendulum bearings.The finite-element model of the full bridge was established based on CSiBridge software.The NSD was simulated by an elastic multisegment line.The friction pendulum bearing and viscous damper were simulated using the bilinear restoring force model and Maxwell model,respectively.Nonlinear time-history analysis was conducted by inputting three seismic waves to investigate the seismic response of the bridge under the novel seismic isolation system.Results show that NSD and viscous damper can effectively reduce the bearing displacement of the long-span and super-long unit continuous girder bridge.The NSD performs better than the viscous damper in terms of controlling the internal force response of the pier and the acceleration response of the beam.The NSD presents a good application prospect in the seismic response control of long-span and super-long unit continuous girder bridges.