Scaffolding is a working platform constructed to ensure the smooth progress of various construction processes. It is categorized by installation location into external and internal scaffolding; by material into wooden, bamboo, and steel pipe scaffolding; and by construction form into upright, bridge, gate, suspended, hanging, cantilever, and climbing scaffolding.

Different types of construction projects require different types of scaffolding. Most bridge support structures use bowl clamp scaffolding, with some using door frame scaffolding. For main structure construction, most use clip joint scaffolding, with the longitudinal spacing of the scaffold uprights typically 1.2~1.8m; the transverse spacing usually 0.9~1.5m.

Scaffolding, compared to general structures, has the following characteristics in working conditions:

1. The load variability is significant.

2. The connection nodes of fasteners are semi-rigid, and the rigidity of the nodes is related to the quality of the fasteners and the installation quality, with significant variation in node performance.

3. Scaffold structures and components have initial defects, such as initial bending of rods, rusting, significant dimensional errors in assembly, and eccentric loading, etc.

4. The connection points to the wall exhibit significant variation in their constraint to scaffolding. There is a lack of systematic accumulation and statistical data for the research of the above issues, and the conditions for conducting independent probability analysis are not met. Therefore, the adjustment coefficient, which is multiplied by the structural resistance and is less than 1, is determined by calibrating against coefficients used in the past. Consequently, the design method adopted in this specification is essentially a combination of semi-probabilistic and semi-empirical approaches. Compliance with the structural requirements specified in this specification is a fundamental condition for design calculations.