塑料温室拱结构雪载工况下极限承载力的非线性有限元分析

Nonlinear finite element analysis of the bearing capacity of arch structure in plastic greenhouse on snow load working condition

该文阐述了应用非线性有限元理论,对塑料温室拱结构在考虑初始缺陷条件下,进行极限承载力分析的方法。初始缺陷的模型是根据一致缺陷模态法,按最小特征值屈曲模态分布,并控制其最大值的方法确定。结构分析考虑双重非线性情况,采用弧长法跟踪整个荷载—位移全过程的平衡路径,确定极限承载力。该文以华东型连栋塑料温室在雪载工况下作实例分析,其计算结果与产品标定的承载力基本吻合,表明该方法具有较好的适用性。

The method of ultimate bearing capacity calculation of the arch structure of plastic greenhouse was presented in the research. The nonlinear finite element analysis theory was applied in the method development. Based on the consistent mode imperfection method, the initial defect model was determined by the least order mode of eigenvalue buckling, and the maximum displacement value. Double nonlinear factor was considered in the structure analysis. To calculate the ultimate bearing capacity, the equilibrium path of the load and displacement using arc-length method was traced. The ultimate bearing capacity of the multi-span plastic greenhouse under snow load in the eastern-China was calculated by the method. The calculated result was close to the production- marked bearing capacity , which showed that the method was suitable.