Scaffolding is a working platform constructed to ensure the smooth progress of various construction processes. It is categorized by its location into outer scaffolding and inner scaffolding; by material into wooden scaffolding, bamboo scaffolding, and steel pipe scaffolding; and by construction form into upright tube scaffolding, bridge scaffolding, gate scaffolding, suspended scaffolding, hanging scaffolding, cantilever scaffolding, and climbing scaffolding.
Different types of construction projects require different types of scaffolding. Most bridge support structures use bowl clamp scaffolding, with some using gate scaffolding. For the construction of the main structure, most use clip joint scaffolding, with the longitudinal spacing of the scaffold uprights typically ranging from 1.2 to 1.8 meters; the transverse spacing usually ranges from 0.9 to 1.5 meters.
Scaffolding, compared to general structures, has the following characteristics in terms of working conditions:
1. The load variability is quite significant.
2. The connection nodes of the fasteners are semi-rigid, and the rigidity of the nodes is related to the quality of the fasteners and the installation, with significant variation in node performance.
3. Scaffold structures and components have initial defects, such as initial bending of rods, rust, large assembly size errors, and eccentric loading, all of which are considerable.
4. The connection points to the wall exhibit significant variation 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 multiplied by the structural resistance is determined by calibrating against previously used coefficients. Consequently, the design method adopted in this specification is essentially a hybrid of semi-probabilistic and semi-empirical approaches. Compliance with the structural requirements specified in this specification is the basic condition for design calculations.
