摘要
为研究大跨半漂浮体系中承式钢管混凝土拱桥黏滞阻尼器参数选取与减震效果,以某计算跨径320 m中承式钢管混凝土拱桥为工程背景,采用MIDAS/Civil软件建立有限元模型,在动力特性分析的基础上提出黏滞阻尼器减震方案,并基于非线性动力时程分析方法研究了黏滞阻尼器的参数选取与减震效果。结果表明:半漂浮体系中承式钢管混凝土拱桥的纵飘振型出现较早,振型参与质量所占比重大,黏滞阻尼器参数选取主要应考虑梁端纵桥向容许位移和阻尼器连接构件所能承受的阻尼力;对相同的阻尼指数,主梁梁端最大纵桥向位移响应随着阻尼系数的增大呈非线性减小,阻尼器轴力随着阻尼系数的增大几乎呈线性增大;阻尼指数在0.2~0.4之间变化时,阻尼指数越大,同时满足梁端位移与阻尼力要求的阻尼系数可选范围越大;设置黏滞阻尼器后,梁端纵桥向位移响应显著减小,拱顶纵桥向位移有所增加,除拱顶处拱肋轴力略有减小外,其余各处轴力、剪力与弯矩均有所增加,但内力响应绝对值不大;研究成果可为同类桥梁减震设计提供参考。
In order to study the parameter selection and damping effect of viscous damper for long-span semi-floating main girder half through concrete-filled steel tubular arch bridge,taking a half through concrete-filled steel tubular arch bridge with a calculated span of 320 m as the engineering background,the finite element model was established by MIDAS/Civil software.Based on the analysis of dynamic characteristics,the damping scheme of viscous damper was proposed.Based on the nonlinear dynamic time history analysis method,the parameter selection and damping effect of viscous damper were studied.The results show that the longitudinal floating vibration mode of semi-floating main girder half through concrete-filled steel tubular arch bridge appears earlier,and the vibration mode takes a significant proportion in the mass.The allowable longitudinal displacement of the beam end and the damping force that the damper connecting members can bear should be considered in the selection of viscous damper parameters.For the same damping index,the maximum longitudinal displacement response of the main beam end decreases nonlinearly with the increase of the damping coefficient,and the axial force of the damper increases almost linearly with the increase of the damping coefficient.When the damping index changes within the range of 0.2-0.4,the larger the damping index is,the larger the optional range of damping coefficient meeting the requirements of beam end displacement and damping force is.After setting viscous damper,the longitudinal bridge displacement response of beam end decreases significantly,and the longitudinal bridge displacement of arch crown increases.Except that the axial force of arch rib at the vault decreases slightly,the axial force,shear force and bending moment at other places increase,but the absolute value of internal force response is small.The research results can provide reference for the seismic design of similar bridges.
作者
彭益华
毛立敏
PENG Yi-hua;MAO Li-min(School of Management Science and Engineering,Guangxi University of Finance and Economics,Nanning 530007,Guangxi,China;Guangxi Communications Design Group Co.,Ltd.,Nanning 530029,Guangxi,China;School of Civil Engineering,Central South University,Changsha 410075,Hunan,China)
出处
《建筑科学与工程学报》
CAS
北大核心
2022年第2期36-43,共8页
Journal of Architecture and Civil Engineering
基金
国家自然科学基金项目(51708559)
广西高校中青年教师科研基础能力提升项目(2021KY0652)。
关键词
钢管混凝土拱桥
减震设计
非线性动力时程分析
黏滞阻尼器
半漂浮式主梁
concrete-filled steel tubular arch bridge
damping design
nonlinear dynamic time history analysis
viscous damper
semi-floating main girder
