基于失效模式的格栅承力筒结构缩比模型研究

Study on Scaled Model of Grid Lattice Cylinder Based on Its Failure Modes

针对工程实际中大尺寸格栅承力筒的缩比模型验证需求,以相似理论为基础,采用方程分析法对格栅承力筒结构轴压下的力学性能进行分析,建立了整体失稳、局部失稳和材料破坏三种失效模式对应的临界承载力方程;利用格栅的等效刚度和临界承载力方程构建缩比模型;最后通过有限元模拟对结构原件和缩比件的力学性能进行对比分析与验证。结果表明建立的缩比方法可以有效反映结构原件的力学性能,可代替大尺寸结构原件用于后续研究。

Grid lattice cylinders have great potentials in aeronautic application due to their excellent mechanical properties such as high strength and light weight. In engineering practice, the scaled model can be used to study the properties of the large - size grid lattice cylinder so as to reduce the difficulties and research cost and shorten the research cycle. O n the basis of similarity theory, a scaled model of grid lattice cylinder was studied through equation analysis. Firstly, the mechanical properties of the grid lattice cylinders under axial compression were analyzed, three failure m o d e s were discussed, and the relationship between the mechanical response and the geometrical p a r a m e-ters of the grid lattice cylinder was obtained. T h e n a scaled model w a s built by equivalent equation of the stiffness and ultimate failure load. Finally, the mechanical properties of both the original struc-ture and the scaled structure were compared and validated through finite element simulation. T h e re-sults showed that the scaled model built in this paper was efficient to validate the properties of the o-riginal structure, so it may be used in experiment research as a substitute of the original structure.