Different appearances

It can be divided into double-layer plate type grid structure, single-layer and double-layer shell type grid structure. The members of the plate type grid and double-layer shell type grid are divided into upper chord members, lower chord members, and web members, which mainly bear tensile and compressive forces; The members of a single-layer shell type truss not only bear tensile and compressive forces, but also bending moments and shear forces. The vast majority of China's grid structure adopts plate type grid structure.

Composition form

The first type is composed of a planar truss system, which includes four forms: two-way orthogonal upright truss, two-way orthogonal oblique truss, two-way oblique oblique truss, and three-way truss.

The second type consists of four pyramid elements, including five forms: upright four pyramid grid, upright empty four pyramid grid, oblique four pyramid grid, chessboard shaped four pyramid grid, and star shaped four pyramid grid.

The third type consists of triangular pyramid elements, which can be divided into three forms: triangular pyramid grid, evacuated triangular pyramid grid, and honeycomb triangular pyramid grid. The shell type grid structure is mainly divided into cylindrical shell type grid, spherical shell type grid, and hyperbolic parabolic shell type grid according to the shell surface form. The grid structure is divided into steel grid, reinforced concrete grid, and composite grid composed of steel and reinforced concrete according to the materials used, among which steel grid is more commonly used.