某钢箱拱人行天桥受力性能分析

Mechanical Performance Analysis of a Steel Box Arch Pedestrian Bridge

随着城市的发展,人车争道的矛盾逐渐增多,使得交通更加拥堵,而人行天桥的出现很好地缓和了这一矛盾。但目前,在大多数人行天桥成桥运营阶段的荷载设计中,仅考虑人群和迎风面较小的风荷载,因此在结构尺寸确认过程中,仅凭工程经验来考虑,往往造成较大的富余。文章以云南某工程的钢箱拱人行天桥为例,采用有限元软件对其受力性能进行分析。在整体受力分析方面,采用梁单元的方法对其进行建模分析,结果表明该桥整体受力性能良好,能够满足正常运营需求;同时对城市钢结构人行天桥最核心的结构自振频率和局部构件的强度、刚度和稳定性进行分析,结果表明该桥满足规范要求,提高了行人的舒适度。

With the development of the city,the contradiction between people and vehicles competing for lanes is gradually increasing,which makes traffic more congested,and the emergence of pedestrian bridges has eased this contradiction.However,at present,in the load design of most pedestrian bridges during the operation stage,only the crowd and the small wind load on the windward side are considered.Therefore,in the process of structural size confirmation,only the engineering experience is considered,which often leads to a large surplus.Taking a steel box arch pedestrian bridge in a project in Yunnan as an example,this paper analyzes its mechanical performance by finite element software.In the overall stress analysis,the beam element method is used to model and analyze the bridge.The results show that the overall stress performance of the bridge is good and can meet the normal operation requirements.At the same time,the natural vibration frequency of the core structure and the strength,stiffness and stability of local components of the urban steel pedestrian bridge are analyzed.The results show that the bridge meets the specification requirements and improves the comfort of pedestrians.