With the continuous advancement of science and technology, the space frame structure is being widely used in the booming construction industry, in public buildings such as airports, waiting halls, gymnasiums, etc., and in industrial plants such as turbine rooms and dry coal sheds in power plants widely used. The space frame structure has the characteristics of large span, light weight, convenient construction and beautiful appearance. At present, there are two main methods of space frame installation: bulk assembly and sliding installation. The following mainly introduces the construction process of sliding installation. A full-scale operation platform of a certain area is set up at the place where the space frame is installed, and the parts are assembled into strip units. The assembled space frame is moved out of the operation platform by using the sliding system, and then the connection is continued. Assemble the strip unit, then slide, and so on until the entire space frame is assembled and slides in place. It is suitable for space frames with large area and long length combined with strip units, especially when the ground space or lifting equipment is limited, the advantages of using the sliding method are more obvious.
The installation process is as follows: structure construction phase → installation preparation → space frame assembly → quality inspection → space frame slippage → inspection and fixation.
1、Structural construction stage
Structural construction such as space frame columns and beams should be completed in strict accordance with the construction drawings, and the verticality of columns and the flatness of beam surfaces should be well controlled. At the same time, when pouring concrete, the embedded parts on the beam and column surface should be embedded according to the design drawings. The specifications, models, elevations, positions of the embedded parts and the flatness of the embedded parts on the beam surface are the focus of quality inspection.
2.1、space frame processing and transportation
Space frame materials are produced and processed by professional manufacturers in strict accordance with the design drawings, and should be numbered according to the drawings. Rods, connecting balls, bearings, bolts, etc. should be treated with anti-corrosion before leaving the factory, and there should be a protective film to prevent paint abrasion. There should be anti-collision protection measures during material transportation. Before installation, select the installation materials according to the design drawings, rod numbers and installation sequence, and classify and stack them nearby.
2.2、Frame acceptance, spring line
Before dismantling the operation rack for frame column beam construction, fix a full-length 12# steel wire rope on the column body on the upper part of the space frame beam, so as to facilitate the operator to hang the safety belt when measuring, springing, and slipping. The steel wire rope is attached to each Wrap 2 turns around the column and tighten it to reduce mid-span deflection. Before installation, check the verticality of the frame column, the position and flatness of the embedded parts on the beam surface, and if there are any defects, they should be dealt with to prevent the space frame from being blocked during the sliding process. Use the theodolite to draw the axis A, B and the center line of the frame column on the beam of the space frame, and mark it with ink lines, so as to judge whether the space frame is offset during the sliding process and whether it is in place at the end.
2.3、Set up the assembly platform
Before construction, comprehensively consider the following factors: the specific situation of on-site cross operations, the location of lifting equipment (tower crane), the influence of site and space conditions, etc., and then choose a suitable location to build the assembly platform. Before setting up the frame, the site should be leveled first (if it is soft fill, it should be tamped first), and then the track wood should be padded, the pad iron should be placed on the plywood, the pole should be erected on the pad iron, and the sweeping pole should be added according to the specification requirements. In order to ensure safety, the operation platform on the top surface is fully paved with double-layer scaffolding, and railings are set around the platform and surrounded by dense mesh safety nets. In addition, under the operation platform, an intermediate isolation layer is added at a height of 12.6m, which is also covered with scaffolding sheets, and the surrounding area between the operation platform and the isolation layer is maintained with a dense mesh safety net. Then seal the lower part of the operating platform with scaffolding to prevent personnel from entering the construction area, so as to prevent rods, ball joints, and other tools from falling and hurting people. Finally, build a 1.5m-wide lifting platform from the side of the 11th axis (or 19th axis) of the operation platform for people to walk or temporarily place tools during construction. Closed to prevent falling objects.