A space frame or space structure is a structure system assembled of linear elements so arranged that forces are transferred in a three-dimensional manner. Space frames can be used to cover large areas with few interior supports. Like the Truss, a space frame or space structure is strong because of inherent rigidity of the triangle; flexing loads (bending moments) are transmitted as tension and compression loads along the length of each strut.
Space frame is typically designed using a rigidity matrix. The special distinctive of the stiffness matrix in an architectural space frame is independent of the angular factors. If the joints are sufficiently rigid, the angular deflections can be minimized.
There are different types of space frames classified into –
a) Space Plane Covers:
Spatial structures composed of Planar Sub-structures
The planes are channeled through the horizontal bars and the shear forces are supported by the diagonals
b) Barrel Vaults:
Has a cross section of simple arch
Usually require the use of tetrahedral modules or pyramids as a part of its unit
c) Spherical Domes
Usually requires the use of tetrahedral modules or pyramids and additional support from a skin
2.Classification by Arrangements of its Elements:
a) Single Layer Grid:
All Elements are placed on the surface approximately
b) Double Layer Grid:
They are commonly used space frame.Elements are organized in two parallel layers with each other at certain distance apart.
The diagonals bars connecting the nodes of both layers in different directions
c) Triple Layer Grid:
Placed in three parallel lines, linked by the diagonals
Almost always flat
They are mostly used for larger span building