空间异型双曲面钢屋盖缺陷稳定性分析及试验研究

Theoretical and experimental study on the stability of steel roof structure of abnormal hyperboloid shell with imperfections

南通体育会展中心钢屋盖为空间异型双曲面,结构高跨比和矢跨比均较小,稳定性分析是其设计中的一个关键问题。本文在体育馆缩尺模型试验基础上,对其钢屋盖结构进行了几何非线性和双非线性稳定分析,分别采用实测缺陷法、一致缺陷模态法、改进随机缺陷法考虑结点位置偏差缺陷的影响。结果表明:实测缺陷法双非线性分析结果是评估体育馆屋盖结构实际安全性的重要依据;一致模态法的临界荷载概率可靠度较低。通过改进随机缺陷法,对该屋盖结构的稳定性能有了比较全面的认识,并定量分析了设计临界荷载和一致模态法分析的临界荷载的可靠性。

The steel roof of Nantong sports and exhibition center is an abnormal hyperboloid.The stability analysis is a key problem in its design.An experimental model of a 1/100 scale is tested carefully.The geometric nonlinear analysis and the dual nonlinear analysis of the steel roof structure are performed.Three methods,including measured imperfections method,consistent mode imperfections method and advanced stochastic imperfections method,are used to investigate the influence of the initial imperfections on the critical load.It shows that the results of the dual nonlinear analysis with measured imperfections method are important reference to assess the actual safety of the roof structure.And the results indicate that the reliability of the critical load of the steel roof structure with consistent mode imperfections is small.It is pointed out that the reliability of both the critical load with consistent mode imperfections method and the design critical load can be evaluated accurately with the use of advanced stochastic imperfections method.