摘要
混凝土网壳结构内部主要承受压应力,因此能够充分发挥混凝土材料的受压性能,但同时也引发了网壳的稳定问题。郑州南站上部雨棚为混凝土多跨连续网壳结构,本文采用大型通用有限元软件ABAQUS,对其进行了整体稳定分析,分析过程考虑了几何非线性和材料非线性,讨论了荷载分布、初始缺陷、施工方式对结构稳定性的影响。对于郑州南站网壳结构,分析结果表明,结构在全跨活荷载下较在半跨活荷载下更易失稳,初始缺陷越大网壳结构越容易失稳,顶棚壳预制或现浇对网壳整体稳定影响不大。在有限元模型中,梁单元由材料用户子程序UMAT建立,而壳单元混凝土采用ABAQUS自带的损伤塑性模型(CDP)。通过分析得出,郑州南站混凝土多跨连续网壳结构稳定性满足规范要求。
The concrete reticulated shell structure mainly bears compressive stress,so it can make full use of the compressive performance of concrete materials,which can also lead to stability problems of reticulated shell structures.The upper canopy of Zhengzhou south railway station is a concrete multi-span continuous reticulated shell structure.In this paper,the general finite element software ABAQUS is used to analyze the overall stability of the canopy.The geometric nonlinearity and material nonlinearity are considered in the analysis process,and the influence of load distribution,initial defects and construction methods on the stability of the structure is discussed.For the reticulated shell structure of Zhengzhou South Railway Station,the analysis results show that the structure is more likely to lose stability under the full span live load than under the half span live load.The larger the initial defect is,the more likely the reticulated shell structure is to lose stability.The prefabricated or cast-in-place roof shell has little influence on the overall stability of the reticulated shell structure.In the finite element model,the material model for beam element is dealt with by user material subroutine(UMAT),while the damage plastic model(CDP)is adopted to shell element.The analysis results show that the stability of the canopy structure of Zhengzhou south railway station meets the requirements of the code.
作者
周鹏飞
刘传平
吴晓涵
宋红召
ZHOU Pengfei;LIU Chuanping;WU Xiaohan;SONG Hongzhao(Department of Disaster Mitigation for Structures,Tongji University,Shanghai 200092,China;Tongji Architectural Design Co,Shanghai 200092,China)
出处
《结构工程师》
2021年第2期36-44,共9页
Structural Engineers
基金
国家铁路集团科技研究开发计划课题(N2019G057)。