From what aspects should the safety performance of steel members be evaluated? How to judge?

Steel structure members are widely used in various steel structure buildings, including steel structure frame, steel truss, steel grid, steel cable structure, cold-formed thin-wall steel structure, light steel structure, steel pile and other types, so how to evaluate the safety performance of steel structure in steel structure buildings? What are the differences of safety evaluation control indexes of steel members in various steel structure buildings?
According to the requirements of the relevant codes, the safety of the steel structure members, according to the bearing capacity, structure and not suitable for bearing displacement or deformation of the identification, each inspected member respectively grade identification; For the safety evaluation of steel structure joints and connecting areas, the grade of each joint and connecting areas should be evaluated according to the two inspection items of bearing capacity and structure. For cold-formed thin-wall steel structures, light steel structures, steel piles, steel structures and other steel structures located in industrial areas with corrosive media, or high humidity, coastal areas, unsuitable bearing corrosion should also be evaluated as an inspection item; The lowest level is then used as the security level for the component.
1. Bearing capacity
When evaluating the safety grade of steel structural members according to the bearing capacity, the grade of each inspection item is evaluated according to the provisions of Table 1, and the lowest grade is taken as the safety grade of member bearing capacity. The checking calculation of steel structure overturning, sliding, fatigue and brittle fracture shall be carried out according to the relevant provisions of the current national code. The checking of nodes and connecting areas shall include the checking of nodes' plates and connecting areas.
Step 2: Structure
When evaluating the safety grade of steel structure members according to the structure, the grade of each inspection item shall be evaluated according to the provisions of Table 2, with the lowest grade as the safety grade of component structure.
3. Not suitable for bearing displacement or deformation
4. It is not suitable for bearing rust
5. Safety assessment of cable components
6. Joint safety evaluation of steel grid structure
7. Additional support, nodes, and connections