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When the steel structure is damaged, we need to find and solve the problem immediately. The main factors of steel structure damage are:

1) the structure's bearing capacity is insufficient due to load changes, overdue service, and changes in codes and regulations;

2) due to all kinds of accidental deformation, distortion, disability and sag of the component, the section of the component is weakened, the rod is warped and the connection is cracked;

3) deformation, cracking and warping of components or joints caused by temperature difference;

4) the section of steel structure members is weakened due to corrosion of chemical substances and electrochemical corrosion;

5) others include design, production, construction errors and illegal use and operation during the service period.

There are three main technical measures for steel structure reinforcement:

1) cross-section reinforcement method: steel is used to reinforce parts or the whole length of the component, and the whole part is made to bear common stress;

2) change the calculation diagram: add additional support, adjust the load distribution, reduce the level of internal force, force displacement on the statically indeterminate structure support, reduce the peak stress;

3) prestressed cable method: use high strength cable to strengthen the weak link of the structure or improve the overall bearing capacity, stiffness and stability of the structure.