When the steel structure is also damaged, we must immediately find and solve the problem, the main factors of steel structure damage are:
1) The structural bearing capacity is insufficient due to load changes, overdue service, and changes in norms and regulations;
2) Components due to various accidents caused by deformation, distortion, disability, depression, etc., resulting in the weakening of component section, rod warping, connection cracking, etc.;
3) Deformation, cracking and warping of components or connections under the action of temperature difference;
4) Corrosion due to the erosion of chemical substances and electrochemical corrosion resulting in the weakening of the cross-section of Steel structure members;
5) Others include mistakes in design, production and construction, and illegal use and operation during the service period.
There are three main technical measures for strengthening steel structures:
1) Section reinforcement method: in the local or along the full length of the member with steel reinforcement, connected into a whole to make it common force;
2) Change the calculation diagram: add additional supports, adjust the load distribution, reduce the internal force level, and force displacement of statically indeterminate structural supports to reduce the stress peak;
3) Prestressed cable method: The use of high-strength cable to strengthen the weak links of the structure or improve the overall bearing capacity, stiffness and stability of the structure.
