基于NVD的半圆式钢桁梁异型斜拉桥抗震性能分析  

Analysis on seismic performance of semicircle steel truss girder special-shaped cable-stayed bridge based on NVD

作　　者：陈爱军[1] 周彦 贺国京[1] CHEN Aijun;ZHOU Yan;HE Guojing(School of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]中南林业科技大学土木工程学院,湖南长沙410004

出　　处：《自然灾害学报》2021年第5期147-154,共8页Journal of Natural Disasters

基　　金：国家自然科学基金项目(51178473);湖南省教育厅科学研究重点项目(19A526);中南林业科技大学高层次人才引进项目(2019YJ036)。

摘　　要：为研究非线性粘滞阻尼器(Nonlinear Viscous Dampers,NVD)的特征参数与不同布设方案对半圆式钢桁梁异型斜拉桥抗震性能的影响。以某景观斜拉桥为研究对象,分别对两种NVD布设方案下的不同阻尼系数、速度指数以及不设阻尼器的ANSYS有限元模型开展了非线性时程分析与抗震随机分析。以桥梁跨中最大位移响应与跨中最大弯矩响应为主要特征点,对比分析了地震荷载激励下桥梁结构的抗震性能,并对抗震效果最佳的NVD布设方案进行了抗震随机分析。研究结果表明:(1)NVD的引入使得桥梁结构在地震荷载激励下所产生的位移响应与弯矩响应均得到了显著的控制;(2)在地震荷载作用下,桥梁跨中最大位移响应、跨中最大弯矩响应与一定范围内的NVD特征参数取值呈负相关,但相比于阻尼系数,速度指数的增大对结构最大位移响应的控制效果更为显著;(3)引入NVD使得抗震随机分析结果中的结构位移响应峰值能够较大概率地保持在一个较低的水平,NVD可以提高桥梁的抗震性能。To research the influence of characteristic parameters of nonlinear viscous dampers(NVD) and different layout schemes on the seismic performance of bridge structure,a semicircle steel truss girder special-shaped cable-stayed bridge was taken as the research object,and the nonlinear time-history analysis and seismic random analysis were carried out on ANSYS finite element model at two types of NVD’s layout schemes with different damping coefficient,different velocity exponent,and without NVD.By selecting the maximum displacement response of structure and the maximum bending moment response of bridge midspan as the main characteristic points,the seismic performance of the bridge under seismic excitation was compared and analyzed.Then,based on the layout scheme of NVDs with optimal seismic effect,the seismic random analysis of the bridge was carried out.The results shows:Firstly,the installations of NVD makes the displacement response and moment response of the bridge under the earthquake excitation significantly controlled.Secondly,the maximum displacement response and the maximum bending moment response excitated by seismic waves in midspan were negatively correlated with the NVD’s characteristic parameters in a certain range,and the increase of velocity exponent had more significant control effect on the maximum displacement response than the damping coefficient.Thirdly,in seismic random analysis,the maximum displacement response of the structure under the control of NVD are on a low level in high probability,and NVD can improve the seismic performance of the bridge.

关 键 词：异型斜拉桥 钢桁梁 非线性粘滞阻尼器 位移响应 弯矩响应 抗震性能 抗震随机分析 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U442.55[交通运输工程—道路与铁道工程]