The main methods of steel structure reinforcement are:
Reduce the load, change the calculation of graphics, increase the original structure of the cross-section and the connection strength, to prevent crack propagation
When there is a mature experience, other reinforcement methods can also be used. Identification of the need to strengthen the steel structure, according to the scope of damage is generally divided into local reinforcement and comprehensive reinforcement.
Local reinforcement is a lack of carrying capacity of the bar or connecting joints at the reinforcement, there are increased cross-section method to reduce the free length of the rod method and the connection node reinforcement method.
Full reinforcement is the reinforcement of the overall structure, there is no change in the structure of the static calculation of the graphic reinforcement method and change the structure of the static calculation of the two types of graphic reinforcement.
Increase or strengthen the support system, but also an effective way to strengthen the structural system.
The method of reinforcement of the original component section is the most costly and most costly method (but often a viable method); the method of changing the calculation diagram is most effective and varied, and the cost is also greatly reduced
1. Before determining the reinforcement plan, the following information should be collected:
(1) the original structure of the completion of the map (including the change map) and acceptance records.
(2) the original steel material report copy or on-site material inspection report.
(3) the original structural components production, installation acceptance records.
(4) the original structural design calculations.
(5) structural or component damage inspection report.
(6) the actual load and reinforcement after the new load data.
2. the main factors of steel structure damage and reinforcement technical measures
2.1 The main factors of steel structure damage are:
(1) structural changes in load, overdue service, norms and procedures lead to structural capacity is insufficient;
(2) components due to a variety of accidental deformation, distortion, disability, depression, etc., resulting in weakened cross-section, bar warping, connection cracking;
(3) under the action of temperature difference caused by component or connection deformation, cracking and warping;
(4) corrosion due to the erosion of chemical substances and electrochemical corrosion caused by weakened steel structure components;
(5) other including the design, production, construction errors and service during the illegal use and operation. This article origin steel alliance
2.2 steel structure reinforcement technology measures are mainly three:
(1) section reinforcement method: in the local or along the full length of steel components to strengthen, even as a whole to make the common force;
(2) to change the calculation diagram: additional support, adjust the load distribution, reduce the internal force level, the statically indeterminate bearing structure forcing displacement, reduce the peak stress;
(3) prestressed cable method: the use of high-strength cable reinforcement structure to enhance the weak links or improve the overall structure of the bearing capacity, stiffness and stability.