2. Classification by Position Relative to the Building:External scaffolding and internal scaffolding.
3. Classification by Purpose:Working scaffolding, protective scaffolding, and load-bearing support scaffolding. Working scaffolding can be divided into structural working scaffolding, decorative working scaffolding, etc.
4. Classification by Structural Assembly Method:Member-assembled scaffolding, frame-assembled scaffolding, lattice-assembled scaffolding, etc.
5. Classification by Number of Vertical Pole Rows:Single-row scaffolding, double-row scaffolding, multi-row scaffolding, full-house scaffolding, full-height scaffolding, special-shaped scaffolding, etc.
6. Classification by Support Method:Ground-supported scaffolding, cantilevered scaffolding, attached lifting scaffolding, horizontally movable scaffolding, etc.
Common Issues in Design
1.Clarification on the definition of heavy-duty scaffolding is required: Generally, if the floor thickness exceeds 300mm, the scaffolding should be designed as heavy-duty scaffolding; if the scaffolding load exceeds 15kN/㎡, an expert demonstration of the design scheme is required. It is necessary to distinguish the parts where the change in steel pipe length has a significant impact on the load: For formwork support, the length from the centerline of the top crossbar to the formwork support point should not be too long, generally, it is appropriate to be less than 400mm. When calculating vertical poles, the top and bottom step distances usually bear the maximum force and should be taken as the main calculation points. If the load-bearing capacity does not meet the requirements, vertical poles should be added to reduce the longitudinal and transverse spacing, or crossbars should be added to reduce the step distance.
2.Substandard materials such as steel pipes, couplers, top supports, and bottom supports are commonly found in domestic scaffolding. In actual construction, theoretical calculations do not take these factors into account, so a certain safety factor should be adopted in the design and calculation.
Common Issues in Construction
-Missing sole plates (ground sweep rods), unconnected joints at longitudinal and transverse intersections, excessive or insufficient distance between sole plates and the ground, etc.;
-Cracked scaffold planks, insufficient thickness, and non-compliance with specifications in lap joints;
-No anti-falling nets installed between internal vertical poles and the wall after the removal of large formworks;
Discontinuous diagonal braces (scissors braces) in the plane;
-No diagonal struts installed for open-type scaffolding;
-Excessive spacing between small crossbars under scaffold planks;
-No rigid internal-external connection for wall-attached members;
-Guardrail spacing exceeding 600mm;
-Loosened couplers, slipping couplers, etc.
Common Issues in Deformation Accidents and Their Handling
1.Local deformation of scaffolding caused by foundation settlement: Set up splayed braces or scissors braces in the horizontal section of the double-row scaffold, with one set installed for every row of vertical poles until reaching the outer row of the deformed area. The bottom of the splayed braces or scissors braces must be set on a solid and reliable foundation.
2.Deflection of cantilevered steel beams supported by scaffolding exceeding the specified value: Reinforce the rear anchorage points of the cantilevered steel beams. After the steel beams are tightened, use steel supports and U-shaped jacking props to support the roof. The gaps between the pre-embedded steel rings and the steel beams must be wedged tightly with wedges. Inspect the
3.steel cables at the outer ends of the suspended steel beams one by one, tighten all of them, and ensure uniform force bearing.Local damage to the scaffolding load-unloading tensioning system: Immediately restore it in accordance with the load-unloading tensioning method specified in the original plan, and correct the deformed components and members. For example, when correcting the outward deformation of the scaffolding: first, install a 5t chain block (come-along) for each span and fasten it to the structure; loosen the rigid tie points; at the same time, tighten each chain block inward until the deformation is corrected; install rigid ties properly; tighten the steel cables at each load-unloading point to ensure uniform force bearing; finally, loosen the chain blocks.
Post time: 2025-12-29 10:43:06