Laboratory and virtual experiments on C-section compression members with semi-rigid connections

Abstract

In this paper results of an ongoing research on cold-formed C-section members are presented. The research aims the development of design methods for structural arrangements directly not covered by the standard, based on laboratory tests and numerical modelling. In the paper laboratory tests on C-section compression members are presented: arrangement, behaviour modes and load-bearing capacities. The behaviour of the specimens as well as the effect of the non-rigid end support provided by the self-drilling screws used to introduce load in the specimens are discussed. A numerical model capable of geometrically and materially nonlinear, imperfect analysis to reproduce the tests is introduced with a focus on the modelling of the connector elements and imperfections. An approach to model self-drilling screws and equivalent geometrical imperfections is presented; the applicability of the model is shown. It is shown, that screw stiffness and geometrical imperfections both influence the stiffness of the models. The ca libration of the model is carried out using the results of the experimental tests introduced previously; the results of these virtual experiments are presented.