自锚式悬索桥减震控制的试验研究

Experimental Study on Vibration Suppression of Self-anchored Suspension Bridge

为研究独塔自锚式悬索桥在纵向设置黏滞阻尼器后的结构地震响应和减震效果,以某独塔自锚式悬索桥为工程背景,按照相似理论,设计制作了1/20大比例缩尺模型,设计了一致输入和行波输入试验工况,进行了在主箱梁与辅助墩之间纵向设置黏滞阻尼器的振动台试验。研究结果表明:在自锚式悬索桥纵向设置参数合理的黏滞阻尼器后,模型桥的纵飘频率变化很小,阻尼比变大,说明黏滞阻尼器对结构提供了一定的阻尼,一致激励工况下,梁端、塔顶位移反应减小,并且主塔底部应力有所减小,具有较好的减震效果;行波激励工况下,行波效应对自锚式悬索桥的结构响应有放大作用,阻尼器在行波激励下起到了很好的减震作用。

In order to study structural seismic response and seismic-reduced effect of the single-tower self-anchored suspension bridge with longitudinal viscous dampers,a single tower self-anchored suspension bridge is used as the engineering background. According to the similarity theory,a 1/20 large scale model is designed. A consistent input and traveling wave input test conditions,shaking table test was carried out to set the viscous dampers longitudinally between the main girders and the auxiliary piers. Research indicates: in the self-anchored suspension bridge longitudinal set of a reasonable viscous dampers,the variable frequency of the model bridge is very small and the damping ratio becomes larger,indicating that the viscous damper provides a certain damping of the structure.Under the same excitation condition,beam end,tower top displacement reaction is reduced,and the stress at the bottom of the main tower is reduced,under the traveling wave excitation condition,the traveling wave has a magnifying effect on the structural response of the self-anchored suspension bridge,the damper plays a very good seismicreduced effect under traveling wave excitation.