​Which sub-projects are more dangerous for steel structures?

Abstract The dangerous sub-projects of Steel structures include: 1. Hoisting, 2. On-site high-altitude welding, 3. High-altitude operations, 4. Purlin installation, 5. Horizontal support installation, and 6. Roof panel installation.

Some projects with higher risk of steel structure:

1. Foundation pit support and dewatering projects

1. Foundation pit (trough) support and dewatering projects with an excavation depth exceeding 3m (including 3m).

 2. Foundation pit (trough) support and dewatering projects that do not exceed 3m but have complex geological conditions and surrounding environment.

2. Earth excavation projects: 

earth excavation projects for foundation pits (troughs) with a depth of more than 3m (including 3m).

3. Formwork engineering and support system

1. Various tool formwork projects: including sliding formwork, climbing formwork, large formwork, flying formwork and other projects. 

2. Concrete formwork support project: erection height 5m and above; erection span 10m and above; total construction load 10KN/㎡ and above; concentrated line load 15KN/㎡ and above; height greater than the horizontal projection width of the support and relatively independent and unconnected components concrete formwork support project. 

3. Load-bearing support system: used for full-floor support systems such as steel structure installation.

4. Hoisting, installation and disassembly projects

1. Lifting and hoisting projects that use unconventional lifting equipment and methods, and the single lifting weight is 10KN or more. 

2. Installation projects using lifting machinery. 

3. Installation and disassembly of lifting machinery and equipment.

5. Scaffolding Project

1. Erection of floor-standing steel pipe scaffolding projects with a height of 24m and above. 

2. Attach the overall and segmented lifting scaffolding projects. 

3. Cantilever scaffolding project. 

4. Hanging basket scaffolding project. 

5. Self-made unloading platform and mobile operating platform project. 

6. New and special-shaped scaffolding projects.

6. Demolition and blasting projects

1. Building and structure demolition projects. 

2. Use blasting demolition engineering.

7. Building curtain wall installation project

1. Steel structure, space frame, and cable formwork structure installation projects. 

2. Manually dug hole pile engineering. 

3. Underground excavation, pipe jacking and underwater work projects. 

4. Prestressed engineering. 

5. Adopt new technologies, new processes, new materials, new equipment and more dangerous sub-projects that do not have relevant technical standards.