Development of methods to take account of structural imperfection in the critical analysis of light metallic structures

Abstract

When calculating a structure, the stresses can be determined by analyzing the first or second order; the choice of method is guided by the potential influence of the deformation of the structure. In general, we can see that the scaffolding and shoring structures, due to their low rigidity (stiffness compared to buildings), come in loads of critical coefficients lower than 3. Their structural defects (imperfections) generate significant second order effects and must be taken into account. The difficulty or inaccuracy remains in the definition and the inclusion of these imperfections in an appropriate way in the calculation. The present study suggests a new definition of imperfection approach and compares the result of the bending moments due to the initial deformations introduced in a structure, according to which fully implements the approach developed or known methods. The new approach is developed using the bends or the deformations of the structure to define the shape of the deformed critical which is considered as a single imperfection. This alternative method changes the approach to Eurocode 3.