大跨度钢结构屋盖落架分析方法

Analysis Methods of Removing Temporary Supports to Large-span Steel Structural Roof

首先对大跨度钢结构屋盖的落架过程进行了简单分析,给出了落架应遵循的基本原则,并提出了“同步协调”和“分组分步”2种落架方式;其次,介绍了落架过程数值模拟的3种计算方法:支座位移法、等效杆端位移法和千斤顶单元法,并详细论述了各自的计算原理及特点;最后,基于ANSYS有限元软件,应用3种落架计算方法对3点支撑悬臂梁及国家体育场进行了落架过程模拟。结果表明,等效杆端位移法和千斤顶单元法是2种合理有效的方法,并可以方便地应用于工程实际中。

Firstly, some basic rules of removing temporary supports from steel structural roof were presented and two basic procedures of removing temporary supports, one is supports lowering simultaneously and the other is group by group and step by step, were also discussed in detail. Secondly, three calculation methods for numerical simulation analysis of removing temporary supports which are support displacement method, equivalent rod bottom-end displacement method and jack element method were introduced. Finally, the process of removing temporary supports was simulated by ANSYS finite element software package for two examples, namely three points support cantilever beam and national stadium. The comparisons of calculation results obtained by using three points support analysis methods mentioned above indicate that equivalent rod bottom-end displacement method and jack element method are rational and effective for an accurate simulation analysis of removing temporary supports to steel structural roof.