1、 Unloading method for steel structure factory columns

When reinforcing or replacing new columns in an unloaded state, the "beam replacement column" method must be adopted.

2、 Steel structure factory building steel column reinforcement method

1. Strengthen the cross-section of the column. Generally, steel plates or sections are used to reinforce the cross-section of columns, which are connected to the original column as a whole through welding or high-strength bolts.

2. Add support. Add support to reduce the free length of the column and improve its load-bearing capacity. Improved the stability of the column while maintaining the same cross-sectional dimensions.

3. Change the calculation diagram to reduce the external load or internal force on the column.

4. Surrounding the steel column with reinforced concrete for reinforcement can significantly improve its load-bearing capacity.

3、 Reinforcement method for column base of steel structure factory building

1. Reinforcement method for insufficient thickness of column base plate

Add column base stiffeners to reduce the calculated bending moment of the base plate. Pour concrete between the column base steel to make the column base plate a rigid block. To increase adhesion, the paint and rust on the surface of the column base should be cleaned thoroughly.

2. Reinforcement method for insufficient anchoring of column base

Add additional anchor bolts. When the concrete foundation is wide, it is used. Drill holes on the concrete foundation, insert additional anchor bolts, pour epoxy mortar or sulfur mortar (hole diameter is the anchor bolt diameter plus 20mm, depth greater than 30d), and wrap the entire column base with reinforced concrete. The new steel bars should be inserted into the foundation and welded to the original steel bars inside the foundation.

4、 Algorithm for testing the bearing capacity of reinforced columns in steel structure factory buildings

The important issue in reinforcement calculation under load state is whether the stress can be redistributed after reinforcement, that is, whether the original stress of the reinforced section can be redistributed to the newly reinforced component section. If it can be redistributed, the sum of the new and old loads can be evenly distributed to the new and old sections. Otherwise, the original load will still be borne by the original section, and the newly added load will be evenly shared by the new and old sections (i.e. the total reinforced section).