Why are steel structure hoisting assembled on the ground

Reliable footholds shall be provided for suspension operation, and protective railings, protective nets or other safety facilities shall be set as appropriate.

The rigging, scaffold, basket, cage, platform and other equipment used for the protective railings must be used only after technical appraisal or verification; the hanging operators must fasten the safety belt.

During the hoisting of steel structure, the components shall be assembled on the ground as far as possible, and the safety measures such as temporary fixation, electric welding, high-strength bolt connection, etc. shall be set. The installation and installation of steel structure should be carried out at the same time, and the removal of these safety facilities should be considered. Before hoisting large components at height, safety facilities for hanging operation shall be set.

There are many factors causing fatigue crack, which are related to design, manufacture and material. However, most of the fatigue cracks are closely related to long-term overload, which is the cumulative result. With the revolution of China's construction technology, the construction speed has been rapidly improved. One story building in three days is no longer a myth. The projects completed in the past few years were completed in a few months. At such a fast speed, we should pay more attention to the standardized operation and maintenance of equipment. On the contrary, the original specialized management institutions, equipment department and machinery department are mostly optimized and simplified, and their functions are greatly weakened, even some companies have no equipment management department at all. In addition, it is not uncommon for some leaders to adopt the strategy of "blocking people but not horses" in order to improve the construction speed. I don't know that "horse" also has tired and long illness, if not carefully fed, nursing will also "horse loss.". The fatigue of steel structure is only a small crack at first, and only when the crack extends to a certain extent, the accident will occur. For example, we often check, find and deal with them in time, which can completely avoid the occurrence of such accidents. The main parts that are easy to fatigue include: the connection between foundation joint and bottom beam, welding joint of main limb or connecting sleeve of diagonal brace or standard section, section of tower body, upper and lower support, rotating tower body, main limb or padeye at the top and tower bottom, etc.