1. Different definitions. Space frame structure is a space structure composed of many bars by nodes and according to the regular geometry.In the grid structure, the double layer or multi-layer flat plate grid structure is called the lattice structure, and the curved grid is called the mesh shell structure.
2. The reticle has a prominent aesthetic feeling.The shell has beautiful architectural shape, whether the building plane, shape and form can give the designer full creative freedom.You can have all kinds of planar forms and surface forms, and you can even get them by cutting and combining surfaces.It can show static beauty, and can be dynamic and beautiful through the cutting of plane and elevation and the change of grid, support and bar.
3. The value of variable load is different.The roof of the space frame, generally not a person, the roof live load standard value is 0.5kn/m2, and the net shell is normally taken 0.3kN/m2 according to the load specification.Due to the different appearance of the net frame and the net shell, the wind load is different due to the different coefficient of wind load.
4. Roof drainage is different.Due to the surface shape of the shell structure, the natural drainage function is formed, and the space frame frame drainage mainly adopts the following methods.
(1) the entire network frame arch, which is good for seismic performance.
(2) the height of the space frame, which resulted in the increase of the number of upper chord and the type of stalk, which made it difficult for the network frame production, but improved the seismic performance of the network frame.
(3) small vertical columns are added on the upper chord nodes, but the small columns need to be checked for earthquake and stability.
5. The calculation length of the rods and the allowable length of length are different. The difference of calculation length is mainly in the calculation length of other abdominal rods, and the relevant specifications can be found.The purpose of the long thin ratio is to prevent the slenderness from being too long and easy to produce the initial bending, which greatly reduces the bearing capacity of the bar.The female of the rod limit length is to ensure that the rod parts have a certain rigidity in the process of making, transporting, installing and using.For the direct bearing load bar, the requirement is more rigid, the specific value can be checked.
6. Different internal forces.The single layer reticulated shell structure has to be made into a new connection, which can deliver bending moment, while the space frame is basically articulated.The flat rack has no horizontal thrust or pull on the support base, while the net shell is generally different, and the shell needs a larger edge member to constrain it.
7. Seismic analysis is different. Space frame: in an area with an intensity of 8 degrees, the structure of the frame is not designed for horizontal seismic calculation, but vertical seismic calculation must be carried out.The horizontal and vertical seismic calculation of the grid structure must be carried out in the area of 9 degrees.Net shell: in a region of 7 degrees, the structure of the shell has no vertical seismic calculation, but the horizontal seismic calculation must be carried out.The horizontal and vertical seismic calculation of the shell structure must be carried out in the area of 8 degrees and 9 degrees.