I will join the steel structure team at the construction site immediately. What are the difficulties and problems needing attention in winter steel structure construction in northern China? I hope my

I will join the steel structure team at the construction site immediately. What are the difficulties and problems needing attention in winter steel structure construction in northern China? I hope my brothers can teach me! 1. Matters needing attention in winter construction of steel structure

1. The fabrication of steel structure and the winter construction of the device shall be carried out in strict accordance with the relevant provisions of winter construction of steel structure.

2. When steel members are manufactured at positive temperature and installed at negative temperature, the shrinkage of members should be considered according to the difference of environmental temperature, and technical measures should be taken to adjust the deviation during construction.

3. Welders who participate in the construction of negative temperature steel structures should be trained in negative temperature welding technology, pass the examination and obtain corresponding certificates.

4. Steel and related connecting materials used at negative temperature shall have quality certificates, and their performance shall meet the requirements of design and product standards.

5. covered electrode used at negative temperature shall not be exposed for more than 2 hours, and it shall be baked again after 2 hours, and the baking times in covered electrode shall not exceed 3 times.

6. The flux should be baked according to regulations before use, so that its water content does not exceed 0.65438 0%.

7. High-strength bolts used at negative temperature shall have product certificate, and the reinspection of torque coefficient and axial force shall be conducted at negative temperature.

8. Water-based coatings shall not be used for coatings used in steel structures at negative temperatures.

9. Shrinkage allowance should be reserved when blanking components, and welding shrinkage and compression deformation should be coordinated with the shrinkage deformation of steel at negative temperature.

10. When assembling parts, they should be unfolded from the inside out in the order specified in the process. During negative temperature assembly, tests should be conducted to determine the welding shrinkage value that needs to be reserved.

1 1. When assembling components, remove rust, burrs, dirt, oil stains, ice and snow and other sundries left within 50 mm of the joint, and keep the joint dry without residual moisture.

12. Multi-layer welding should be adopted when welding steel plates over 9mm at negative temperature. The welds should be surfacing layer by layer from bottom to top, and each weld should be welded at one time. If welding is interrupted, the welding defects should be removed before welding again. It is forbidden to strike an arc on the welding substrate.

13. When the steel structure is installed on site, if it snows or the wind speed is above 6m/, a protective shed will be erected.

14. Unqualified welds shall be removed and re-welded, and the welding shall be carried out in accordance with the provisions of welding technology for negative temperature steel structures.

15. When the ambient temperature is lower than 0℃, the coating process test shall be carried out before the anticorrosive paint is applied. When painting, the rust, oil stain and burr on the surface of the component should be removed and the surface should be kept dry. Do not brush on snowy days or when there is thin ice on the parts.

16. Anti-skid measures should be taken when transporting and stacking steel structures in winter. The site for stacking parts should be flat and solid, without puddles and ice on the ground. When the components of the same model are stacked, the components should be kept horizontal, and the shim should be placed on the same vertical line to prevent the components from sliding.

17. Before the installation of steel structure, the quality of steel structure should be reinspected as required under the condition of negative temperature, and the components omitted in production and deformed during transportation and stacking should be repaired and corrected on the ground.

18. When hoisting steel members with steel wire ropes, anti-skid pads should be added, and the connecting plates hoisted at the same time with the members, fixtures required by equipment personnel, etc. should be tied firmly with ropes.

19. According to the temperature conditions, prepare the installation sequence diagram of steel members, and install them in strict accordance with the specified order during construction.

20. Prepare the welding process of steel structure installation, and both ends of the components shall not be welded at the same time.

2 1. Before installation, remove the ice, snow and dew on the surface of the parts, but do not damage the coating.

22. Columns and beams installed at negative temperature shall be corrected immediately, and their positions shall be corrected immediately and permanently fixed. The components of the device should form a stable space system on that day.

23. When installing the high-strength bolt connection device, there must be no ice and snow on the friction surface of the parts, and no contact with dust, oil pollution and other stolen goods.

24. The installation quality of steel structure at negative temperature should not only meet the requirements of GB50250-95, but also be inspected and accepted according to the design requirements.

2. Construction measures in rainy season

1. During rainy day construction, temporary protective shed shall be erected, and rain shall not fall on the hot weld. If the welding part is wet, it must be wiped with a dry cloth and dried by oxyacetylene flame before welding, and the joint should be dry without residual moisture.

2. When hoisting, if there is water on the assembly, it should be removed before the equipment, but the coating should not be damaged. When connecting the device with high-strength bolts, the friction surface of the component should be clean, and there should be no water drops, and it should not get caught in the rain and come into contact with dirt and oil stains.

3. Parts in rainy days cannot be painted.

4. Rainy days and strong winds above level 5 cannot be used for roof insulation construction.

5. In rainy days, due to humid air, covered electrode should be moisture-proof and baked. The same covered electrode should not be baked more than twice, and the management personnel should make baking records in time.

6. In case of windy weather, large components such as columns, main beams and supports should be corrected immediately, and permanent fixation should be carried out immediately after the position correction is correct to prevent unilateral instability. The components of the device should form a space stabilization system that day.

3. Civilized construction measures:

1. The industry requires all materials and accounting (construction plan, safety education, safety disclosure, safety inspection, electrician's day patrol record, pre-shift speech record and accounting) to be complete and tidy, and the certified records of special operations should be practical and realistic, and the division of safety responsibilities should be clear.

2. Wear a safety helmet when entering the site, wear a safety belt when working high above the ground, support a safety net according to regulations, have a protective shed at the entrance and exit, and have a safe passage in a narrow space.

3. Electrical equipment adopts three-level control and two-level protection (main brake box, distribution box, switch box, distribution box and switch box are equipped with supporting electric shock maintainer). Brake box standardization, circuit standardization, recording electrician patrol and roll record.

4. This project is provided with a black calendered board fence of not less than 2m, which is used for on-site civilized construction management. There are obvious propaganda slogans at the scene, and color codes that meet the standards are hung at dangerous places.

5. There is a flat and clean channel at the site, without blockage and water accumulation, and the construction wastewater is reasonably discharged through the drainage ditch.

6. Civilized construction will not disturb people, strictly control construction noise, and stop construction after 10 in the afternoon.

7. Do not occupy roads in violation of regulations inside and outside the site, build or stack things in violation of regulations, cause fire and traffic accidents, damage public facilities in violation of regulations, and pollute the environment, and cooperate with relevant road departments and health supervision departments.