单向纵坡斜拉桥阻尼器设置研究

Study on dampers setting of a cable-stayed bridge with single-way longitudinal grade

以一预应力混凝土单向纵坡斜拉桥———南平闽江大桥为对象,在拟定采用液体粘滞阻尼器控制主梁纵向位移的前提下,通过建立的精细有限元模型,进行施工阶段、运营阶段和弹性地震响应分析,从而确定阻尼器主要参数指标.对阻尼器数量与设置位置进行了分析和优化,在综合考虑主梁纵向位移减小量、墩底内力增加量、经济成本和方便施工养护的前提下,给出最优的阻尼器布置方案.研究结果表明,在两主塔下横梁与主梁之间各布置2个阻尼器,可使主梁的纵向位移减小0.139 m,并使主墩墩底的弯矩和剪力大幅降低.施工实测数据结果证明了阻尼器良好的工作性.

Based on applying liquid viscous dampers to control the longitudinal displacement of main girder for a PC cable-stayed bridge with a single-way longitudinal grade,Min River Bridge in Nanping,the finite element model is established to analyze the bridge under construction,service,and earthquake,and then the main parameters of dampers are determined.Besides,the best solution of dampers setting is achieved after analysis and optimizing of dampers number and location considering the longitudinal displacement reduction of main girder,inner force increment in pier bottom,cost and convenience of construction and maintenance.The results show that,when two dampers are placed between lower cross beam and main girder for each tower,the main girder longitudinal displacement is reduced by 0.139 m,and the bending moment as well as shearing force decrease significantly.The validity of dampers is verified by the actual measurement during construction.