To ensure the stability and safety of scaffolding, systematic measures must be taken from multiple aspects, including design, materials, erection, use, and management. Specific measures are listed below:
First, ensuring stability and safety during the scaffolding design phase.
Scaffolding load calculation and structural design
- Identify load types: Consider permanent loads such as construction personnel, materials, and equipment, as well as variable loads such as wind and seismic loads. Accurately calculate according to the “Uniform Technical Standard for Safety of Scaffolding in Construction” (GB 51210) and other standards.
- Optimize the structural form: Select the appropriate scaffolding type (e.g., double-row floor-standing, cantilever, climbing frame, etc.) based on the building height and plan shape. Ensure that parameters such as vertical pole spacing, crossbar step spacing, and sweeping pole placement meet design requirements. For example, vertical pole spacing for floor-standing scaffolding is typically no more than 1.5 meters, and step spacing is no more than 1.8 meters.
- Anti-overturning design: Connect the scaffolding to the main structure through wall anchors (e.g., rigid tie structures). The anchor spacing should be no more than 4 meters in height and no more than 6 meters horizontally to prevent the scaffolding from overturning. Specialized design for special scenarios
- For ultra-high scaffolding (height > 50 meters), large-span scaffolding, or scaffolding in areas with concentrated loads (e.g., material platforms), special designs and expert review are required. If necessary, additional reinforcement measures such as steel supports and unloading devices should be implemented.
Second, Scaffolding Material Quality Control
1. Core Material Standards
- Steel Pipe: Use Q355B grade high-frequency welded steel pipe, with a diameter of 48.3mm ± 0.5mm and a wall thickness of 3.6mm ± 0.36mm. Bent, rusted, or cracked steel pipe is strictly prohibited.
- Fasteners: Use malleable cast iron or cast steel fasteners with an anti-slip bearing capacity ≥ 8kN and an anti-destruction bearing capacity ≥ 10kN. The tightening torque (40-65 N·m) and appearance quality of the fastener bolts must be inspected upon arrival.
- Scaffolding: Wooden scaffolding boards must be ≥ 50mm thick, and steel scaffolding boards must be ≥ 2mm thick. Damaged or deformed scaffolding boards are strictly prohibited. Scaffolding boards must be fully laid and securely fastened.
2. Scaffolding Material Testing and Acceptance
Steel pipes and fasteners must be sampled and inspected for mechanical properties (such as tensile strength and bending strength) and appearance quality. Unqualified materials must not be used.
Third, Standardized Control of the Scaffolding Erection Process
1. Scaffolding Foundation Treatment and Support Structure
- Foundation Reinforcement: The foundation of ground-based scaffolding must be leveled and compacted. Full-length scaffolding boards or steel backing plates (≥ 5mm thick) must be laid. Drainage measures must be implemented to prevent foundation settlement from causing the scaffold to tilt. – Cantilever Support: The cantilever beams of cantilever scaffolding should be made of I-beams of size 16 or higher, with the anchor end length ≥ 1.25 times the cantilever length. They should be secured to the building structure using pre-buried U-bolts with a bolt diameter ≥ 16mm.
2. Key Points of Scaffolding Construction
Vertical and Horizontal Connections: Vertical deviation of vertical beams should be ≤ 1/200 of the scaffolding height, horizontal deviation of horizontal beams should be ≤ 10mm, and the clearance of sweeping beams from the ground should be ≤ 200mm to ensure verticality and horizontality of the scaffolding.
3. Scissor Bracing and Diagonal Bracing Installation
Double-row scaffolding should be installed with continuous scissor braces on the outside, with a width of 4-6 spans (≤ 9 meters). The diagonal braces should be angled 45° to 60° with the ground, and their bases should be fixed to the foundation or vertical beams. For scaffolding heights greater than 24 meters, vertical diagonal braces should be installed every 5-7 spans along the inside longitudinal direction to enhance the integrity of the scaffolding. Working Floor Protection: Scaffolding boards should be fully laid and secured, with 1.2-meter-high guardrails and 180mm toeboards installed on the outside. A dense safety net (mesh density ≥ 2000 mesh/100 cm²) should be hung underneath to prevent falls and impacts.
4. Wall Anchor Construction
Wall attachments should be installed according to the designed spacing. Rigid steel pipe connections (such as through-wall bolts and clamps) are preferred; flexible wire ties are strictly prohibited. If wall attachments are not feasible, alternative measures such as cantilever load relief should be employed.
Fourth, Safety Assurance in Scaffolding Use and Management
1. Scaffolding Load Limits and Uniform Distribution
Clearly define the load standards for scaffolding (e.g., ≤ 2kN/m² for decoration scaffolding and ≤ 3kN/m² for structural scaffolding). Overloading of scaffolding with materials or concentrated stacking of heavy objects (such as mixers or rebar) is strictly prohibited. Materials should be evenly distributed to avoid deformation of the scaffolding due to excessive localized loads.
2. Daily Inspection and Maintenance
- Regular Inspections: Inspect the scaffolding at least once a week, focusing on issues such as vertical column settlement (≤10mm), loose fasteners, damaged scaffolding boards, and missing wall attachments. Any hidden dangers must be immediately corrected.
- Special Condition Inspections: After strong winds (≥ Force 6), heavy rain, or heavy snow, the scaffolding must be thoroughly inspected, snow and water removed, and damaged components repaired.
3. Demolition Operation Standards
Before demolition, a specific plan must be prepared, specifying the demolition sequence (from top to bottom, layer by layer; simultaneous demolition is strictly prohibited). A warning area must be established and personnel assigned to oversee the demolition. Dismantled components must not be thrown; they must be sorted, stacked, and promptly removed to prevent collapse caused by uneven stress on the scaffolding.
Fourth, Scaffolding Safety and Emergency Measures
1. Safety Protection Facilities
Establish a protective shed (≥3 meters in length and ≥ the width of the scaffolding) at the entrance and exit of the scaffolding, with a double layer of scaffolding covering the entire roof to prevent falling objects. Gaps (greater than 150mm) between the scaffolding and the main structure must be closed with scaffolding boards or safety nets to prevent falls.
2. Emergency Management
Develop a scaffolding collapse emergency plan, equip emergency rescue equipment (such as jacks and wire ropes), and conduct regular drills to ensure a rapid response in the event of an incident.
Post time: Sep-15-2025