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

Different types of construction projects require different types of scaffolding. Most bridge support scaffolding uses bowl clamp scaffolding, with some using gate scaffolding. For the main structure construction, most use clip scaffolding for ground scaffolding; the longitudinal spacing of the scaffolding uprights is generally 1.2~1.8m; the transverse spacing is generally 0.9~1.5m.

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

1. The load variability is relatively large.

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, rust, significant assembly size errors, and eccentric loading, all of which are considerable.

4. The connection points to the wall exhibit significant variability in their constraint on scaffolding. Research on the above issues lacks systematic accumulation and statistical data, and does not meet the conditions for independent probability analysis. Therefore, the value of 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 semi-probabilistic and semi-empirical approach. Compliance with the structural requirements specified in this specification is a fundamental condition for design calculations.