The Chinese Steel Structure Code stipulates that structures with a span of 60m or more are long-span structures.
How to construct a large-span steel structure? Let me share with you several commonly used construction methods for large-span steel structures.
In order to ensure the smooth splicing of on-site units, the high-altitude in-situ unit installation method should first pre-assemble several units in the factory. The focus of this method is the reasonable division of hoisting units. Generally, the following points should be grasped:
1. The size of the unit depends on the crane capacity and structural form selected. For example, for a large-span steel truss structure, the block location should not be in the middle of the truss span;
2. For the beam-column structure, it is generally recommended to set the segmented position at the reverse bending point in the design;
3. For grid and reticulated shell structures, generally block or strip schemes can be used;
4. The unit must be a self-contained system with sufficient stability, rigidity and strength.
Overall lifting installation method
The overall lifting installation method is an installation method in which the structure to be installed is assembled on the ground or at a suitable floor projection position, and then the “lifting system” is used to raise the overall formed structure to the design elevation.
When the height of the large-span steel structure is high, which is not conducive to erecting the supporting tire frame and the lifting steel structure has a regular shape, the overall lifting construction method can be one of the options.
Unsupported installation method of span cantilever steel structure
Suitable for cantilevered steel structure with high rigidity, good stability and high height.
With this construction method, the overhanging section will buckle under the influence of its own weight.
The trouble caused by this is that the installation coordinates of the components are unknown.
When there is a requirement for the installation configuration or there is a closure situation, the position of the structure during the construction process Shape control is one of the biggest technical problems, which is directly related to whether the structural configuration at completion can meet the requirements and whether the overhanging section can be closed smoothly.
In recent years, most steel structure buildings have unique shapes, which have brought many difficulties to construction and installation. Deeply understand the composition of these steel structures, use construction resources and the company’s proprietary technology to design the most suitable installation plan according to local conditions.
