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, door, suspended, hanging, cantilever, and climbing scaffolding.

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

Ladders offer the following characteristics compared to general structures in terms of working conditions:

1. The load variability is quite 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, rust, significant dimensional errors in assembly, and eccentric loading, all of which are considerable.

4. The connection points with the wall exhibit significant variability in their constraint on the scaffolding. Research on the aforementioned issues lacks systematic accumulation and statistical data, and does not meet the conditions for independent probability analysis. Therefore, the adjustment coefficient multiplied by the structural resistance is determined by calibrating with 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 the basic condition for design calculations.