Study On Geometric Constitution And Mechanical Behavior Of Cylindrical Kelvin Polyhedron Space Frame Structure

The basic units to constitute polyhedron are the polyhedrons with the ability of filling three-dimensional space firmly. The basic geometric model of "Water Cube" was built based on Weaire-Phelan polyhedron composition. Apart from semi Weaire-Phelan polyhedron, there are some other polyhedrons and polyhedron combinations forming, which can also form density packing to fill whole three demensions space, such as the Cube, the Truncated Octahedron, the Rhombic dodecahedron and the combination which consist as the ration of 1:1:3 by the Great Rhombicuboctahedron, the Truncated Octahedron and the Cube can form dense accumulation body. In this thesis, the structure formed by the Truncated Octahedron (the Kelvin polyhedron) is systematically analyzed.First of all, geometric constitution of Kelvin polyhedron space frames is studied by graph analytic method. Kelvin polyhedron space frames structure is formed by combination, array, rotation and cutting of the Kelvin polyhedral cells.Then, this thesis analyzed static behavior of plate polyhedron frame structures. It is chosen the plate polyhedral frame model for static analysis. Under the condition that the models with the same span, the influence generated by the positions of the cutting planes, boundary condition and angle of rotation on the structure's static behavior is discussed in this dissertation.Besides, this dissertation systematically analyzed static behavior of cylindrical Kelvin space frame structure. Cylindrical Kelvin space frame was bent from the plate one, and its static behavior was systematically finite element analyzed. The influence generated by the positions of the cutting planes, boundary condition, angle of rotation and distribution of load is discussed with circumstance in this paper.Furthermore, this paper introduced nonlinear finite full-range analysis theory and method of reticulated shell structure. It also studied on instability morphology and stability of cylindrical Kelvin space frame structure by analyzing eigenvalue buckling and nonlinear stability. Then, buckling mode of the structure, load-deflection curves which based on geometric nonlinearity and stability ultimate loading capacity of cylindrical Kelvin space frame structure can be obtained.Above all, this dissertation particularly studied on geometric constitution and mechanical behavior of cylindrical Kelvin space frame structure, therefore, some meaningful conclusions can be reached. The research conclusions are valuable and instructive in large-span space structure system and stability design and analyze. At the end of this paper, some fields that need to be further studied are put forward so that this new structure should be widely accepted and applied.