Geometrical Modelling And Structural Behavior Of Cable-stiffened Single-layer Latticed Domes Of Pentagonal And Hexagonal Meshes

Single-layer latticed dome with pentagonal and hexagonal meshes is a combination of polygon grid shell.Compared with common triangular latticed shells,the advantage is to increase the transparency and has good architectural effect.Due to all meshes are planar pentagonal or hexagonal,especially suitable for glass roofs or membrane structure,which can be easily fabricated and installed.In order to solve difference problem of the planar shear stiffness of the hexagonal grid,each hexagonal mesh should be braced by diagonal cross cables.In this way,grid shells are composite structures formed by flexible cables and stiff bars.At present,there are similar buildings abroad,but research at home is still in its infancy.However,with the development of public buildings,the new structure has a very good application prospect.Based on the literature at home and abroad,the method of model creating,the basic static mechanical behaviors and the static stability behaviors will be studied in this paper,This paper includes main contents as follows:By analyzing the geometry characteristic of combination polyhedron and solving the problem of non-coplanar,a modeling method is proposed,which is threw triangulation,projection,plane truncation basing on regular icosohedron.The finite element software 3D3 S is adopted to analyze the static mechanical behaviors of the structure with and without cable stiffened.The results showed that the cable to improve the rigidity of structure.Some parameters about static mechanical behaviors are adopted,such as,different load cases,area of steel bars,area of cables,prestress of cables are considered,in order to investigate its effect on stress and the maximum nodal displacements of the structure.The results showed that in order to make the structure to achieve optimal performance,a reasonable proportion relationship between parameters shoud be determined.Using dual non-linearity FEM program ANASYS15.0,the static stability behaviors of thegrid shell is studied with the parameters mentioned above.Study of complete loading displacement curve for latticed shell under the full-span uniformly distributed vertical load,the influence on ultimate bearing capacity of cable stiffened latticed shell of area of cables,f/d,area of steel bars and different initial imperfection were studied.The results show that,the critical capacity of grid shells is sensitive to the imperfection.The installation of the structure should try to reduce the harm of initial imperfection.