1. The load variability is large;
2. The fastener connection node is semi-rigid, and the rigidity of the node is related to the quality of the fastener and the quality of the installation, and the performance of the node is greatly variable;
3. The initial defects of the scaffold structure and components, such as the initial bending and rust of the rod, the size error of the erection, the eccentricity of the load, etc. are all large;
4. The connection point with the wall has a large variation on the binding of the scaffold. The research on the above problems lacks systematic accumulation and statistical data, and does not have the conditions for independent probability analysis. Therefore, the structural resistance multiplied by the adjustment coefficient less than 1 is determined by calibration with the safety factor used in the past. Therefore, the design method adopted in this specification is essentially semi-probabilistic and semi-empirical. The scaffolding meets the structural requirements specified in this specification is the basic condition for design calculation.
No. 9
Post time: Jun-18-2020