上海光源工程主体结构分析

Analysis of the main structure of Shanghai Synchrotron Radiation Facility

上海光源工程显著特征为:由8片异型曲面组成的异型钢屋盖支承在由钢筋混凝土径向框架梁、环向预应力混凝土梁、钢筋混凝土柱和钢-混凝土劲性圆柱形成的混合框架结构体系上。除常规的结构分析外,更充分考虑工程中所特有的微振动控制要求,以满足精密工艺设备的正常使用,因此在建模分析时分别着重考虑风荷载以及温度作用的影响。对于风荷载,不仅进行风洞试验,得出该结构风压分布以负压为主的结论,更应用结构风振响应计算程序,得出了结构等效静力风荷载。而对于温度作用,采取抗-放相结合的思路,采用分级加载方式寻找结构的薄弱环节。除此之外,采用振型分解反应谱法对地震作用进行详细的分析和归纳。最后通过分析结果,总结各种作用下的设计经验,特别是异型钢屋盖风荷载以及温度作用的计算经验,可供同类工程参考。

Shanghai Synchrotron Radiation Facility is a key scientific project for the 11th national ＂Five-Year Plan＂. The marked feature of the building is that the irregularly shaped steel roof is made up of eight irregular curved surfaces that are supported by a mixed-frame structure that is constituted of reinforced concrete radial frame-beams, circumferential pre-stressed concrete beams, reinforced concrete columns and robust steel-concrete cylindrical colunms. In addition to structural analysis, the specific requirements of micro-vibration for the normal operation of fine processing equipments are also considered. Therefore, wind loading and temperature influence are considered in the modeling analysis. As tor the effect of wind buffeting on the structure, wind tunnel tests are conducted to conclude that the structure is mainly subject to negative pressure, and a wind-induced vibration response calculation procedure is employed to give the equivalent static wind load. With regard to temperature effect, the concept of resist-release is adopted, and in order to find the weak link of the structure, the method of incremental loading is used. The capability of structural resistance to earthquake is analyzed in detail by using the mode decomposition response spectrum method. The design experiences under various load cases are summarized, in particular, the experience on how to consider and calculate the wind load and temperature effects on the irregularly shaped steel roof can serve as a reference for similar projects.