Influence of nonstructural components on roof diaphragm stiffness and fundamental periods of single-storey steel buildings

The stiffening effect of nonstructural roofing components on the in-plane shear stiffness of metal roof deck diaphragms was studied. Tests were performed to determine the properties of the non-structural roofing materials and the typical diaphragm connectors. A linear elastic FE model was used to establish stiffness values for common diaphragm configurations, and the results were applied to evaluate the impact of nonstructural roofing elements on the fundamental period of vibration of single-storey steel buildings. The shear stiffness increase due to the nonstructural components was found to be more pronounced for the flexible steel deck diaphragms. The influence on the period of vibration was negligible for most of the buildings studied.