Stabilisation of Steel Structures by Diaphragm Action of Trapezoidal Sheeting

The main idea behind stabilisation by diaphragm action is to create a deep beam thatcan resist horizontal loads acting on a structure. It is achieved by connecting the sheetingto the primary structure of the roof so that the edge beams resist the bending momentthrough normal stresses and the sheeting resists the shear force through shear stresses.An essential assumption of a functional diaphragm system is a sufficient connectionbetween the sheeting and the primary structure.In this thesis, the global behaviour of a diaphragm, as well as possible failure modesof sheeting of different thicknesses, are investigated.A laboratory experiment is conducted in the first part of the thesis. In the experiment,two types of self-drilling screws in combination with three different plate thicknesses aretested in shear. Slip flexibility of the screws is evaluated based on the experiment andcompared to flexibilities according to European Recommendations for the Application ofMetal Sheeting Acting as a Diaphragm.In the second part of the thesis, a finite element simulation is performed on two structuresto investigate the global behaviour of the diaphragm. The experimental results are,additionally, implemented into the finite element model.In the last part, hand calculations are performed based on analytical formulas given inEuropean Recommendations for the Application of Metal Sheeting Acting as a Diaphragmand the maximum horizontal displacement of the structure is compared to the FEAresults