2008奥运会羽毛球馆弦支穹顶预应力张拉模拟施工过程分析研究

对于大跨度弦支穹顶结构,预应力张拉施工过程实际上是几何体系由机构(准机构)变为可承担设计荷载的结构体系过程。该类结构体系的安全控制有别于常规结构体系,它需要对结构的设计状态即最终使用状态进行控制,同时应研究预应力张拉施工过程中结构的力学性能,并对结构几何成形过程中的安全性进行控制。本文以2008奥运会羽毛球馆弦支穹顶屋盖为研究对象,应用分步一次加载法和单元生死法两种不同的计算方法对弦支穹顶结构的预应力施工进行全过程模拟计算,分析了在预应力施工过程中结构位移、环索内力和径向拉杆内力变化规律,确认了张拉施工过程的安全性;得出分步一次加载法时结构力学响应大于单元生死法时结构力学响应的结论;证明弦支穹顶整体结构设计采用分步一次加载法是偏安全的。

Simulating analysis of prestressing construction process of the suspend-dome of the badminton gymnasium for 2008 Olympic Games

For the large-span suspend-dome structure,prestressing construction process is the one where the geometric system changes from mechanism or quasi-mechanism into structure system which is capable of undertaking design load.The safety control of this structure system is different from conventional ones.It requires control of the design state namely the ultimate service-state.Simultaneously the structure mechanical property of the prestress tensioning process should be studied,and the safety in the geometric forming process of structure should be controlled.In this paper,the suspend-dome of the badminton gymnasium for 2008 Olympic Games is taken as the research subject by simulating the whole process of prestressing construction with two different calculation methods,analyzing the changing characteristic of shape,internal force and node displacement,and affirming the safety during the construction process.The study indicates that the structural mechanics response by stepped entirely loading method is more than that of element birth-death method.It proves the practicality of stepped entirely loading method usually used in simulating analysis of engineering construction process and the safety of stepped entirely loading method in suspend-dome design.This paper may serve as a good reference for future practice.