There is a steel column with a total length of 40.45m. The factory is divided into four sections. The factory is pre-assembled and shipped to the site. Before the installation on site, in view of the large number of butt welds on site, in order to minimize the high-altitude welding operations, the elevation will be 3.500 - 18.830. The m steel column is assembled on the ground with the first lifting unit, and the 18.830 - 36.700m steel column is assembled on the ground into the second unit.

The ground splicing scheme is designed as follows:

1. Assembly site setting In order to ensure the accuracy of component assembly, the assembly error is prevented due to the uneven settlement of the tire frame during assembly, and the assembly site requires flat compaction. According to the actual optimal position of the hoisting and the maximum size of the steel structure, try to choose the nearest hoisting area for reasonable arrangement. As shown in the figure below, the steel column is assembled on the site floor plan, and the black arrow represents the crane route.

2, component assembly site stacking 1 assembly segment using 80t crawler crane unloading, seating, assembly; 2 steel column assembly, should be under the assembly section under the sleeper, the pad points are evenly distributed along the assembly length; the foundation of the bolster is required to be compact, all Pad the occipital epithelium with a level gauge.

3. Assembling the erection of the assembled tire frame Because the site of the project has not been completed yet, the roadbed box plate can be rented as the assembly platform. When assembling the tire frame, the steel road base box plates should be laid first and connected to each other to form a rigid platform. After the platform is laid, the elevation line, the inspection line and the fulcrum position are placed to form a field-shaped control network, and the acceptance is submitted. Then set up the frame and set the frame and the braces according to the elevation at the fulcrum, as shown in the figure below. The height of the tire frame is about 500mm. After the tire frame is erected, it must not be obviously shaken, and it can be used after passing the experience. In order to prevent the deformation of the tire frame caused by the settlement of the rigid platform, the observation point of the settlement of the tire frame should be established beside the tire frame. If there is any change, it should be adjusted in time, and the welding can be carried out after the settlement is stable.

4. Assembling process is shown in the following figure. 5. Steel column assembly According to the size of the steel column, first measure the laying line of the assembled tire frame, adjust the elevation of the surface of the assembled tire frame, and control the placement of the steel column on the surface of the assembled tire frame. line. The segmented steel column is placed on the tire frame for measurement and review, and then the steel column is measured. The distance between the main control column and the support surface of the steel column, the distance from the cow leg to the support surface, and the distortion of the column body are measured. After the retesting is correct, use the jack to tighten the column body and the assembled tire frame, first carry out the positioning welding, and then carry out the welding.