[提要]重庆出口加工区卡口根据建筑造型的需要，设计为两榀斜交放置的大跨度箱形钢拱结构，而两相交钢拱间采用了较柔性的钢管相连。由于此钢拱结构的刚度分布极不均匀，对抗震及抗风设计均不利。在结构计算中，采用大型通用有限元分析程序ANSYS，通过提取不同振型及频率，运用振型分解反应谱法对其动力特性及地震反应进行了分析。

[关键词]钢拱结构 动力特性 有限元分析

Abstract: The tollgate of Chongqing Export Industrial Park was designed to be a pair of sloped arches intercrossing in space, and linked by a row of steel tubes in order to satisfy specified requirements of architect. The structure rigidity is not uniform, so it is in a disadvantageous condition when imposed by wind or earthquake loads. A numeric model of space arch was established to calculate its behavior under static and climatic loads by using the ANSYS software. The authors discuss problems encountered during applying spectrum analysis, and gave some advice.

Keywords: space steel arch; dynamic character; finite element method