摘要
为研究异型斜拉桥结构安全,静、动力以及抗震性能是否满足规范要求,以某大跨人行异型斜拉桥为工程背景,采用MIDAS Civil有限元分析软件,结合桥梁施工方法,对结构进行了考虑混凝土的收缩、徐变、温度等作用的静力特性及动力特性、空气动力稳定以及抗震性能分析。结果表明:塔、梁各截面承载力均满足规范要求;结构基本周期比较短,能减少结构的地震位移,但对桥塔底部受力不利,主梁竖向弯曲的第1阶频率不符合规范(大于3Hz)要求,需要进行特殊设计,自振特性表现出明显的相互耦合的特点,随着频率的提高,结构扭转所占比重增大,对该桥的横向稳定不利;空气动力稳定良好;在E1地震作用下,结构的应力响应较小,结构刚度较大。
To study the structural safety of long span irregular-shape pedestrian cable-stayed bridge and to check if the static, dynamic and seismic performance of the bridge can meet the relevant requirements in the codes, an actual pedestrian cable-stayed bridge of the same type was cited as an example. By means of the finite element analysis software MIDAS Civil and with reference to the construction methods to be used for the bridge, the static and dynamic characteristics, the aerodynamic stability and seismic performance of the structure were analyzed, taking into account of the action of concrete shrinkage, creep and temperatures. The results of the analysis in- dicate that the bearing capacity of various sections of the pylon and girder of the structure can meet the requirements in the codes, the basic period of the structure is short and can reduce the displacement of the structure caused by earthquake, but it is unfavorable to the force conditions of the pylon footing. The 1st order frequency of vertical bending of the main girder does not meet the requirements （greater than 3 Hz） in the codes and should be specially dealt with in the design. The natural vibration of the structure presents obvious mutual coupling characteristic and with the increase of frequency, the proportion of the structural torsion will increase and will be unfavorable to the lateral stability. The aerodynamic stability of the structure is good and under the earthquake El, the stress response of the structure is little and the rigidity is great.
出处
《桥梁建设》
EI
CSCD
北大核心
2012年第4期45-50,共6页
Bridge Construction
基金
郑州市科技领军人才培育计划(096SYJH23105)~~
关键词
斜拉桥
人行桥
有限元法
静力学
动力学
抗震
cable-stayed bridge
pedestrian bridge
finite element method
statics
dynamics
seismic resistance
