壹定发

The project is located in the new and old kinetic energy conversion pilot area of Jinan City, Shandong Province, with a total construction area of 1.2 million square meters, including a net exhibition area of 510000 square meters. It is the world's largest exhibition center with a net exhibition area and a landmark project in the new and old kinetic energy conversion pilot area of Jinan, of which the largest exhibition hall is hall N1.

The roof steel structure of N1 exhibition hall adopts inverted triangle space three-dimensional truss structure, which is composed of 11 main trusses and 2 secondary trusses. The main truss has a span of 117m, a height of 6m, a width of 4m, and a maximum self weight of about 240 tons, belonging to a few non prestressed system exhibition halls. For the hoisting and assembly of large-span structures exceeding 100 meters, the total station is used to monitor the key points in the whole process, simulate the assembly process through BIM modeling, preview various situations, establish the ground plane control coordinate system and elevation measurement control system, and set up high-precision special assembly jig. At the same time, set the camber value of the coordinates of the key parts of the full truss members to ensure that the deformation of the assembly and hoisting links is controlled with♏in the minimum, and avoid the deformation during and after installation. In order to meet the roof design of the project with the corrugated shape of the Yellow River, the three-dimensional truss is designed as an irregular curve shape, and there are many kinds of intersection angles between the members of the truss, so the welding construction is very difficult. Controlling the welding sequence of the members is the key project to ensure the reduction of deformation in the truss assembly process. The team strictly evaluates, selects welding operators with first-class welding qualification, controls the welding sequence of truss members, and adopts the segmented symmetrical and balanced welding method to ensure the truss assembly quality.