The quality of construction in steel structure engineering directly affects the overall project quality. Enhancing control over project quality requires a stronger focus on the quality of construction processes. There are three main methods for steel structure construction: 1. Whole Assembly Method Lanzhou Steel Structure Processing The whole assembly method involves first assembling the truss on the ground into a complete unit, and then using lifting equipment to elevate it to the designated position for fixation. This method requires no tall assembly supports, minimizes high-altitude work, and facilitates welding quality, but necessitates heavy-duty lifting equipment with complex technology. Hence, it is particularly suitable for steel mesh trusses with ball joints, especially those with more components like three-way trusses. Depending on the equipment used, the whole assembly method can be further divided into methods like multi-crane lifting, pole lifting, jack lifting, and jack jacking. 2. Multi-Crane Lifting Method This method is used for medium and small truss structures that are not excessively high or heavy. Before installation, the truss is assembled out of position on the ground (i.e., the assembly position is offset from the installation axis to avoid column locations). Then, using multiple cranes (usually crawler cranes or truck-mounted cranes), the assembled truss is lifted as a whole to above the column tops, repositioned in the air, and then lowered and fixed in place. 3. High-Altitude Assembly Method The high-altitude assembly method for steel trusses involves first setting up assembly supports at the designated positions, and then lifting individual components (or sections) of the truss to the空中 design position using cranes, where they are assembled on the supports. This method may not always require large-scale lifting equipment, but requires a significant amount of assembly supports and a high degree of high-altitude work. It is therefore more suitable for steel trusses with bolted connections and made of section steel, or steel trusses with bolted spherical joints. Some steel trusses are still constructed using this method today.