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Winter construction measures for steel structure engineering:

1. Steel structure fabrication and installation Winter construction is strictly carried out in accordance with the winter construction regulations for steel structures.

2. When the steel components are installed above or below zero degrees Celsius, the shrinkage of the components should be considered according to the difference in ambient temperature, and measures to adjust the deviation should be taken during construction.

3. Electric welders who participate in the construction of steel structures below zero degrees Celsius should be trained in the negative temperature welding process and have the corresponding certificate of operation.

4. The steel and related connecting materials used under negative temperature shall be accompanied by a quality certificate, and the performance shall meet the requirements of the design and product specification standards.

5. The electrode used below zero degrees Celsius shall not exceed 2 hours, re-bake for more than 2 hours, and the number of baking of the electrode shall not exceed 3 times.

6. The flux is baked as specified before use, so that the water content does not exceed 0.1%.

7. High-strength bolts used below zero degrees Celsius must have a product certificate and re-test the torque factor and axial force at negative temperature.

8. Water-based paints shall not be used for coatings used in steel structures below zero degrees Celsius.

9. When the component is cut, the shrinkage allowance should be reserved. The amount of weld shrinkage and compressive deformation should be coordinated with the shrinkage deformation of the steel below zero degrees Celsius.

10. When assembling the components, expand the group from the inside to the outside in the order specified by the process, and test the negative temperature group to determine the shrinkage value of the weld to be reserved.

11. When assembling the components, remove the rust, burrs, dirt, oil, ice and snow from the seams of 50mm, and keep the joints dry without residual moisture.

12. Below zero degrees Celsius For welding of steel plates above 9mm, multi-layer welding shall be used. The welds shall be welded from bottom to top, and each weld shall be welded once. If the welding is interrupted, the welding defects shall be removed before re-welding. It is strictly forbidden to lead the arc on the welding base metal.

13. When the steel structure is installed on site, if it is snowy or the wind speed is above 6m/s, set up a protective shed.

14. Unqualified welds are removed from re-welding and welded in accordance with the welding procedure for steel structures at negative temperatures.

15. When the ambient temperature is lower than 0 °C, the coating process test should be carried out before applying the anti-corrosion coating. When painting, the rust, oil stain, burr and other materials on the surface of the component must be cleaned and the surface should be kept dry. Do not perform painting work on snowy days or when there is thin ice on the components.

16. In the winter, when the steel structure is piled up, anti-slip measures are taken, and the piled up parts are flat and solid without water, and there is no ice on the ground. When stacking the same type of components, the components should be level and the horns placed on the same vertical line to prevent the components from slipping.

17. Before the installation of the steel structure, according to the requirements under the condition of negative temperature, the quality of the steel structure shall be re-inspected, and the components that are deformed during the production inspection and transport stacking shall be repaired and corrected on the ground.

18. According to the temperature conditions, prepare the steel component installation sequence chart, and install it strictly in the prescribed order.

19. According to the temperature conditions, prepare the steel component installation sequence chart, and install it strictly in the prescribed order.

20. Prepare the steel structure installation welding process, one end of one component shall not be welded at the same time.

21. Remove ice, snow, and dew on the surface of the component before installation, but do not damage the coating.

22. The column and main beam installed at negative temperature are immediately corrected. The position correction is correct and immediately fixed permanently. The components installed on the same day should form a stable space system.

23. When the high-strength bolt joint is installed, the friction surface of the component shall not have snow and ice, and shall not touch the dirt, oil and other pollutants.

24. The installation quality of the steel structure under negative temperature shall be inspected and accepted according to the design requirements, in addition to the requirements of the “Code for Construction and Acceptance of Steel Structure Engineering”.