On construction sites, scaffolding serves as the core support system for working at heights, and its acceptance quality directly determines construction safety and project progress.

I. Main Structure: Rigid Constraints of Scientific Computing

1. Standard scaffolding parameters: Vertical spacing of uprights ≤ 2m, horizontal spacing ≤ 1.5m (JGJ130 Table 6.1.1-1), vertical spacing of longitudinal horizontal members ≤ 1.8m, spacing of transverse horizontal members ≤ 2m.
Case study: In a certain project, the spacing of the uprights exceeded 10%, resulting in a 35% decrease in the overall rigidity of the scaffolding structure, which ultimately led to tilting under wind load.

II. Verticality of Upright Posts: Millimeter-Level Precision Control

When checking the verticality of upright posts, there are clear allowable deviation values ​​at different stages, corresponding to specific inspection tools. Specifically:

1. For every 1m of upright post height, the allowable deviation is ±2mm, measured using a theodolite or plumb line.

2. When the total height of the scaffolding is less than or equal to 30m, the allowable deviation is ±50mm, also measured using a theodolite or plumb line.

3. If the total height of the scaffolding is greater than 30m, the allowable deviation is ±75mm, and the inspection tool is still a theodolite or plumb line.

According to actual measurement data, in one project, the verticality deviation of the upright posts exceeded the limit by 20%, resulting in a 1.8-fold increase in lateral displacement of the scaffolding structure. This situation poses an extremely significant safety hazard.

III. Setting of Small Horizontal Braces: Key Nodes for Load Transfer

1. Node Construction Requirements: The small horizontal braces must be rigidly connected to the vertical posts using right-angle couplers. The torque value at the node must reach 40-65 N·m (JGJ130 Table 4.3.5). An additional small horizontal brace should be added under the scaffolding planks of the working platform, forming a “three-bar support” system, which can reduce the single-point concentrated load by 40%.

2. Connection Process:
The overhang length of the small horizontal braces should be controlled within 100-150 mm (JGJ130 Figure 6.2.2). Excessive length can easily lead to bending moment exceeding the limit.

IV. Fastener Management: Details Determine Success

1. Material Inspection: Fasteners must be free of cracks and pores. A 100% visual inspection is required, along with sampling for anti-slip performance testing (P≥8kN). If the rejection rate exceeds 5%, the entire batch will be returned.

2. Usage Specifications: Right-angle fasteners are used for vertical connections, and swivel fasteners are used for non-vertical connections. Mixing of different types of fasteners is strictly prohibited. Fasteners with a rust depth greater than 0.3mm must be scrapped.

Conclusion: Acceptance testing is the last line of defense for safety. Scaffolding acceptance testing requires the establishment of a “three-level inspection and three-level verification” system: team self-inspection, project re-inspection, and company specialized inspection; verification of calculation sheets, verification of component parameters, and verification of joint structures. Special attention should be paid to increased monitoring of scaffolding settlement during rainy seasons (once daily, with an allowable deviation of ≤10mm).

Industry Warning: A construction site experienced a partial collapse of scaffolding due to the failure to replace corroded fasteners, resulting in three serious injuries. This accident directly exposed the underlying problem of superficial acceptance testing procedures.