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What are the classifications of the grid

更新時(shí)間:2020-12-18 15:05:39?點(diǎn)擊:37228 ? Grid Knowledge

Different shapes 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 the double-layer shell type grid are divided into upper chord, lower chord and web members, which mainly bear tension and pressure; the members of the single-layer shell type grid, in addition to bear the tension and pressure, also bear Bending moment and shear force. At present, most of the grid structures in China use plate grid structures. The first type of composition is composed of a plane truss system. There are four forms of two-way orthogonal orthographic grid, two-way orthogonal diagonal grid, two-way diagonal diagonal grid and three-way grid. The second category is composed of quadrangular pyramid units. There are five forms of positive quadrangular pyramid grids, positive quadrangular pyramid grids, diagonal quadrangular pyramid grids, checkerboard quadrangular pyramid grids and star-shaped quadrangular pyramid grids. The third category is composed of triangular pyramid units, and has three forms: triangular pyramid grid, evacuated triangular pyramid grid and honeycomb triangular pyramid grid.

Shell type grid structure is divided into cylindrical shell type grid frame, spherical shell type grid frame and hyperbolic parabolic surface shell type grid frame according to the shell surface form. The grid structure is divided into steel grids, reinforced concrete grids and combined grids composed of steel and reinforced concrete according to the materials used. Among them, steel grids are used more frequently.