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1. Cross truss system

The first category is the truss structure composed of two or three groups of plane trusses, which is called cross truss system (as shown in the figure). This is one of the simplest and earliest forms of grid structure. It is developed and evolved on the basis of cross beam. The upper and lower chord of this kind of net frame are of equal length. Abdomen bar can be designed as "pull rod system" commonly, namely long rod (inclined rod) pull, short rod (vertical rod) press press, inclined rod and chord include Angle appropriate between 40 degrees to 60 degrees. Among them, the vertical bars are Shared by each group of plane trusses. This kind of net is worn commonly have 2 kinds of form.

The cross truss system is divided into two - way truss and three - way truss (as shown in the figure).

Two, triangular pyramid system network frame

The second category is suitable for buildings of square, rectangle, triangle, trapezoid, hexagon, octagonal and circular plane shapes.

Which is divided into: triangular cone frame, empty triangular cone frame, honeycomb triangular cone frame.

Three, the quadrangle system network frame

The third category is composed of four Angle cone structure, there are five forms, respectively: square quadrangle cone frame, square quadrangle cone frame, diagonal quadrangle cone frame, chessboard shaped quadrangle cone frame and star shaped quadrangle cone frame.

Four, hexagonal pyramid system network frame

The fourth category is the hexagonal pyramid (heptahedron) composed of the grid structure, known as the hexagonal pyramid system grid. Its basic unit is six strings, six strings of hexagonal cone (can be inverted or positive). One main form of this kind of net frame is hexagon pyramid net frame.