ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
31 Installation Scheme Selection The steel structure roof construction of this project has the following characteristics: (1) The whole steel structure project covers a large area, has a large number of components, has a large construction silk-mounted working surface (2) The steel structure hoisting period is urgent (3) The working radius of the installation equipment required for the weight of the roof structure is large, the installation height is more than 40 meters, and the installation is difficult (4) The lower part of the roof is large. The completed concrete stand structure has a large distribution area, so the selection of crane requires that the construction of condensate form cross operation, so the construction coordination requirements are high. 5) The project is partially a three-storey space truss structure, whose spatial stiffness differs greatly between the installation stage and the whole shaping stage. There are many restrictions on the silk-mounting method. Based on this situation, the plan of building full-scale scaffolding, which has great influence on the lower concrete construction, has been eliminated and the roof has been divided into several assembling units. After assembly on the ground, a large crawler crane is used to hoist it from outside the field. Combined with the installation scheme of high altitude inlay bulk, Lang's subarea construction and block loading are carried out.
This scheme not only ensures the construction quality but also meets the construction progress, but also reduces the field assembly scheme 3.2.1 for other professional projects. In the field assembly, according to the joint characteristics of the project and the hoisting scheme drafted on the spot, the field assembly is divided into two parts: 1. rail truss segment assembly 2. welded ball grid block assembly. Assemble. 3.2.2 The assembling of track truss segments weighs about 200 tons per track. The segments are divided according to the lifting weight. The track truss in the northern area is divided into nine segments. The southern area is divided into eight segments. The weight and number of segments are shown in Figure 2 below. Each three segments of track truss are assembled together for pre-assembly. After checking the docking errors, the docking marks are made. After removing the first two silk assembling segments and using the third lifting segment as the medium, the following assembling units are positioned and accurately controlled, that is, 3+1 "assembling form. This method can meet the requirements of the overall accuracy control of components. The assembling of track truss is carried out on a special platform. The center lines of upper and lower chords and web members are drawn on the platform, and the supporting tyres are set up. The frame and the frame are set up in the form of steel pipe pillars and cantilevered positioning brackets. Then the upper and lower chord members are installed to assemble the upper and lower chord culms from the middle to the two ends respectively. After the assembly of the upper and lower chord culms, the belly grooves are assembled and then welded. The welding is carried out by using Co2 gas shielded welding. The welding is symmetrical from the center to the two ends, and the lower chord is welded first and then the upper chord is welded. String, to ensure that the truss produces upward deflection, UT flaw detection and local correction after welding.
After the truss segment assembly is completed, the self-inspection shall be carried out and submitted to the supervisor for acceptance and inspection. After passing the inspection, the truss segment will be moved to the installation position by using the assembly machine. Attached is Figure 3.