1. The fasteners are unqualified (material, wall thickness); the fasteners are damaged when the bolt tightening torque does not reach 65N.m; the fastener tightening torque is less than 40N.m during erection. “Safety Technical Specifications for Fastener Type Steel Pipe Scaffolding in Construction” 》JGJ130-2011.
3.2.1 Fasteners should be made of malleable cast iron or cast steel, and their quality and performance comply with the provisions of the current national standard “Steel Pipe Scaffolding Fasteners” GB15831. Fasteners made of other materials should be tested to prove that their quality complies with the provisions of this standard. Can be used later.
3.2.2 The fastener shall not be damaged when the bolt tightening torque reaches 65N·m.
7.3.11 Paragraph 2 stipulates: The tightening torque of bolts should not be less than 40N.m and should not be greater than 65N.m
2. Steel pipes are corroded, deformed, drilled, etc. Table 8.1.8 No. 3 steel pipe outer surface corrosion depth ≤ 0.18mm. 9.0.4 It is strictly prohibited to drill holes in steel pipes.
3. The wall thickness of the steel pipe is insufficient.
3.1.2 Scaffolding steel pipes should be φ48.3×3.6 steel pipes, and the maximum mass of each steel pipe should not be greater than 25.8kg. Appendix D steel pipe outer diameter is 48.3mm, the allowable deviation is ±0.5, the wall thickness is 3.6mm, the allowable deviation is ±0.36, and the minimum wall thickness is 3.24mm.
4. The foundation is not solid and flat, bricks are placed under the poles, or even suspended in the air, and the pads are too thin and too short.
7.2.1 The construction of scaffolding foundations and foundations should be carried out according to the load of the scaffolding, erection height, soil conditions of the erection site, and the relevant provisions of the current national standard “Construction Quality Acceptance Code for Building Foundation Engineering” GB50202.
7.3.3 Paragraph 2 stipulates that the padding shall be made of wood with a length of not less than 2 spans, a thickness of not less than 50mm, and a width of not less than 200mm.
5. The foundation is not level, hardened, and sinks.
7.2.1 The construction of scaffolding foundations and foundations should be carried out according to the load of the scaffolding, erection height, soil conditions of the erection site, and the relevant provisions of the current national standard “Construction Quality Acceptance Code for Building Foundation Engineering” GB50202.
7.2.2 The compacted fill foundation should comply with the relevant provisions of the current national standard “Code for Design of Building Foundations” GB50007, and the gray soil foundation should comply with the relevant provisions of the current national standard “Code for Construction Quality Acceptance of Building Foundation Engineering” GB50202.
6. Basic water accumulation.
7.1.4 The erection site should be cleared of debris, the erection site should be leveled, and drainage should be smooth.
7.2.3 The elevation of the bottom surface of the pole pad or base should be 50mm to 100mm higher than the natural floor.
7. The distance between the poles is not set according to the design requirements, and the poles at the corners are missing.
Paragraph 2 of Article 5.2.10. When the step distance, longitudinal distance of poles, horizontal distance of poles, and spacing of connecting wall parts of the scaffolding change, in addition to calculating the bottom pole section, it is also necessary to calculate the maximum step distance or maximum longitudinal distance of poles, horizontal distance of poles, Check the vertical pole sections at the distance between the connecting wall parts and other parts.
8. The length of the pole is wrong.
6.3.5 Except for the top step on the top floor, the joints of each step on the other floors must be connected with butt fasteners when extending the poles of single-row, double-row, and full-floor scaffolding.
9. The bottom of the pole is suspended in the air
There should be no accumulation of water in the foundation, paragraph 2 of Article 8.2.3, no looseness in the base, and no hanging poles.
10. When the pole foundations are not at the same height, the sweeping pole is set incorrectly
6.3.3 When the scaffolding pole foundations are not at the same height, the vertical sweeping pole at the high place must be extended two spans to the lower place and fixed to the vertical pole. The height difference should not be greater than 1m. The distance from the axis of the pole above the slope to the slope should not be less than 500mm.
11. The vertical poles of the outer frame are supported on the cantilevered components of the building, and there are no corresponding reinforcement measures.
5.5.3 For scaffolding erected on building structures such as floors, the bearing capacity of the supporting building structure should be calculated. When the bearing capacity requirements cannot be met, reliable reinforcement measures should be taken.
12. The horizontal rod is not on the main node
6.2.3 A transverse horizontal rod must be installed at the main node, fastened with right-angle fasteners and removal is strictly prohibited.
The distance between the center points of each fastener at the main node of paragraph 9 in Table 8.2.4 is ≤ 150mm.
13. The sweeping pole is set higher than 200mm from the ground.
6.3.2 Scaffolding must be equipped with vertical and horizontal sweeping poles. The longitudinal sweeping pole should be fixed on the vertical pole no more than 200mm from the bottom of the steel pipe using right-angle fasteners. The horizontal sweeping pole should be fixed to the vertical pole immediately below the longitudinal sweeping pole using right-angle fasteners.
14. The horizontal sweeping rod is missing
6.3.2 The horizontal sweeping rod should be fixed to the vertical pole immediately below the longitudinal sweeping rod using right-angle fasteners. Each node must be equipped with a horizontal sweeping rod and must not be missing.
15. No wall fittings or scissor supports are provided
The function of the connecting wall parts is to prevent the scaffolding from overturning under the action of wind load and other horizontal forces, and the opposite poles serve as intermediate supports.
16. Irregular installation of wall-connecting parts
6.4.1 The location and quantity of scaffolding wall parts should be determined according to the special construction plan.
The connecting wall parts in paragraph 1 of Article 6.4.3 should be set close to the main node, and the distance away from the main node should not be greater than 300mm.
17. Incorrect setting of flexible wall-connecting parts
6.4.6 Wall-connecting parts must be constructed to withstand tension and pressure. For double-row scaffolding with a height of 24m or more, rigid wall fittings should be used to connect to the building.
18. The scissor supports are not set or are not set completely.
6.6.3 Double-row scaffolds with a height of 24m and above should be equipped with scissor braces on the outside; single-row and double-row scaffolds with a height below 24m must be installed on the facade with an interval of no more than 15m at both ends, corners and in the middle of the outside. , each set up a scissor brace and should be set up continuously from bottom to top.
7.3.9 Scaffold scissor braces and double-row scaffolding transverse diagonal braces should be erected simultaneously with vertical poles, longitudinal and transverse horizontal poles, etc., and should not be installed late.
19. The overlapping length of the scissor brace is less than 1m, and the protruding length of the rod end is less than 100mm.
Paragraph 2 of 6.6.2 stipulates that the extension length of the scissor brace diagonal pole should be overlapped or butt jointed, and the overlap should comply with the provisions of paragraph 2 of Article 6.3.6 of the specification; Paragraph 2 of 6.3.6 When the length of the vertical pole is overlapped, The overlap length should not be less than 1m and should be fixed with no less than 2 rotating fasteners. The distance from the edge of the end fastener cover to the rod end should not be less than 100mm.
20. The scaffolding boards on the working floor are not fully paved, stable, and solid.
6.2.4 The installation of scaffolding boards should comply with the following regulations: The scaffolding boards on the working floor should be fully paved, stable, and solid.
The scaffolding boards in paragraph 1 of Article 7.3.13 should be fully paved and firmly laid, and the distance from the wall should not be greater than 150mm.
The scaffolding probe should be fixed on the supporting rod with a galvanized steel wire with a diameter of 3.2mm.
21. Probe board appears when laying scaffolding board
6.2.4 The setting of scaffolding boards should comply with the following regulations: When the scaffolding boards are butted and laid flat, two transverse horizontal rods should be installed at the joints. The extension length of the scaffolding boards should be 130 mm~150 mm. The sum of the extension lengths of the two scaffolding boards should not be It should be greater than 300mm; when the scaffolding boards are overlapped and laid, the joints should be supported on the horizontal poles, the overlap length should not be less than 200mm, and the length extending out of the horizontal poles should not be less than 100mm.
The scaffolding board probe in paragraph 2 of Article 7.3.13 shall be fixed on the supporting rod with a galvanized steel wire with a diameter of 3.2mm.
22. The scaffolding is far away from the wall and there are no protective measures.
7.3.13 Scaffolding boards should be fully paved and firmly laid, and the distance from the wall should not be greater than 150mm.
23. The safety net is damaged
9.0.12 Single-row, double-row scaffolding, and cantilevered scaffolding should be fully enclosed with a dense-mesh safety net along the periphery of the frame body. The dense-mesh safety net should be installed on the inside of the outer pole of the scaffold and should be firmly tied to the frame body.
24. Irregular construction of ramps
Article 6.7.2 Paragraph 4: Railings and toe-stops should be installed on both sides of the ramp and around the platform. The height of the railings should be 1.2m and the height of the toe-stops should not be less than 180mm.
Paragraph 5 of Article 6.7.2: Wall fittings should be installed at both ends of the material conveying chute, the periphery, and the end of the platform; horizontal diagonal bars should be added every two steps; scissor braces and transverse diagonal braces should be set up.
Article 6.7.3 Paragraph 3: An anti-slip wooden strip should be installed every 250mm-300mm on the scaffolding boards of pedestrian ramps and material conveying ramps, and the thickness of the wooden strips should be 20mm-30mm.
25. Centralized stacking on scaffolding
Post time: Apr-24-2024