Simplified design of nonlinear damper parameters and seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers  

作　　者：Huihui LI Lifeng LI Rui HU Meng YE 

机构地区：[1]College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China [2]Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering,Shenzhen University,Shenzhen 518060,China [3]College of Civil Engineering,Hunan University,Changsha 410082,China

出　　处：《Frontiers of Structural and Civil Engineering》2024年第7期1103-1116,共14页结构与土木工程前沿（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.51978257 and 52278176)。

摘　　要：Viscous dampers are widely used as passive energy dissipation devices for long-span cable-stayed bridges for mitigation of seismic load-induced vibrations.However,complicated finite element(FE)modeling,together with repetitive and computationally intensive nonlinear time-history analyses(NTHAs)are generally required in conventional design methods.To streamline the preliminary design process,this paper developed a simplified longitudinal double degree of freedom model(DDFM)for single and symmetric twin-tower cable-stayed bridges.Based on the proposed simplified longitudinal DDFM,the analytical equations for the relevant mass-and stiffness-related parameters and longitudinal natural frequencies of the structure were derived by using analytical and energy methods.Modeling of the relationship between the nonlinear viscous damper parameters and the equivalent damping ratio was achieved through the equivalent linearization method.Additionally,the analytical equations of longitudinal seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers were derived.Based on the developed simplified DDFM and suggested analytical equations,this paper proposed a simplified calculation framework to achieve a simplified design method of nonlinear viscous damper parameters.Moreover,the effectiveness and applicability of the developed simplified longitudinal DDFM and the proposed calculation framework were further validated through numerical analysis of a practical cable-stayed bridge.Finally,the results indicated the following.1)For the obtained fundamental period and longitudinal stiffness,the differences between results of the simplified longitudinal DDFM and numerical analysis were only 2.05%and 1.5%,respectively.2)Relative calculation errors of the longitudinal girder-end displacement and bending moment of the bottom tower section of the bridge obtained from the simplified longitudinal DDFM were limited to less than 25%.3)The equivalent damping ratio of nonlinear viscous dampers and the applied loading frequ

关 键 词：cable-stayed bridges viscous dampers simplified analytical model equivalent damping ratio seismic mitigation 

分 类 号：TU352.1[建筑科学—结构工程]