Space frame structure characteristics, classification and installation methods

1. The characteristics of the space frame structure The definition of space frame structure-a spatial structure formed by connecting multiple rods through nodes in a certain space frame form. The space frame structure construction speed is fast. The space frame structure components, whose size and shape are largely the same, can be mass-produced in factories, with good quality and high efficiency, and at the same time they do not compete with civil engineering. Therefore, the on-site workload is small and the construction period is shortened. The space frame structure transfers the load by the axial force of the rods, and the material strength is fully utilized, which saves steel and reduces its own weight. A good space frame design, the amount of steel used is close to the steel content of the reinforced concrete structure under the same conditions, so that a large amount of concrete can be saved, and the self-weight can be reduced by 70-80%. Compared with ordinary steel structures, it can be Save 20-50% of steel. The seismic performance of the space frame structure is good. Due to the light weight of the space frame structure, the seismic force generated during an earthquake is small. At the same time, the steel has good extensibility and can absorb a large amount of seismic energy. The space frame has a large spatial rigidity, and the structure is stable and will not collapse. So it has excellent seismic performance. The space frame structure is light and handy. It can cover planes of various shapes, and can be designed into various body shapes with beautiful and generous appearance. The space frame structure can be used as the roof of buildings such as stadiums, theaters, exhibition halls, waiting halls, stadium stands, hangars, two-way large column space frame structures and workshops. The disadvantage of the space frame structure is that the number of rods converging on the node is large, and the production and installation are more complicated than the planar structure. 2.The space frame structure classification The first type is composed of a plane truss system. There are four types of two-way orthogonal orthographic space frames, two-way orthogonal diagonal space frames, two-way diagonal diagonal space frames and three-way space frames; The second type is composed of quadrangular pyramid unit space frame structures. There are five types of positive quadrangular pyramid space frames, positive quadrangular pyramid space frames, diagonal quadrangular pyramid space frames, checkerboard quadrangular pyramid space frames and star-shaped quadrangular pyramid space frames form; According to different shapes, the space frame structure can be divided into double-layer plate-type space frame structure, single-layer and double-layer shell-type space frame structure. The members of the plate type space frame and the double-layer shell type space frame are divided into upper chord, lower chord and web members, which mainly bear tension and pressure; the members of the single-layer shell type space frame, in addition to bear the tension and pressure, also bear Bending moment and shear force. At present, most of China's space frame structure adopts plate space frame structure. The plate space frame structure is in the form of composition.

3.the installation method of the space frame structure 1.The high-altitude bulk method is a very simple grid installation method. The space frame is directly installed on the supporting structure on the installation platform, without the need for large machinery. According to the structural characteristics and site conditions, the installation platform usually adopts full house scaffolding or mobile scaffolding. The choice of this method should fully consider the economy of scaffolding and the impact on the total construction period and construction cross-operations. 2. The sliding method is to use the traction device to pull the installed net frame on the slide rail in place and form it in place. The slip method is divided into single slip method and cumulative slip method. The choice of sliding method is usually due to site restrictions, and it is used when mobile scaffolding cannot be erected. 3. The hoisting method is to use hoisting equipment to separate or hoist the space frame into place. Different hoisting methods can be selected according to the structural characteristics, site conditions and equipment conditions. The successful implementation of the hoisting plan requires a high level of experience and skills for the hoisting operation team. For a space frame with a large volume and an irregular shape, its economic indicators are quite ideal. 4. The comprehensive installation method is to use the above three or two of the installation methods for space frame installation construction under the premise of fully analyzing the site conditions.