Stability analysis of different types of steel scaffolds

Scaffolds are temporary structures commonly used in construction to support various types of loads. Recently their collapse is becoming more common as shown by the number of accidents and injuries reported. The paper analyzes the main flaws and imperfections that could lead to the collapse of the scaffoldings. The study has been focused at the numerical level on three different types of steel scaffoldings: (i) joint tubes, (ii) multidirectional and (iii) prefabricated systems, which are commonly used in Italy. Several finite element simulations under different loading conditions on three types of steel scaffoldings have been performed, taking into account the imperfections during the assembly at the construction site, the base boundary conditions and the effects of lateral restraint arrangement. Finally, the study proposes an empirical formula to identify the critical load of different types of steel scaffoldings based on the number of story levels and the type of boundary conditions.