Numerical Modelling of Single‐span Portal Frames

Abstract Portal frames are a common form of structural system used to create efficient wide‐span enclosures. Over the past few decades, the design of portal frames has evolved in the direction of longer, lighter and taller structures, while cladding systems have become more substantial. Although this allows larger spaces, it can also result in heightened structural challenges, such as increased frame flexibility, a greater portion of the load being borne by the cladding and greater differential thermal movement. This has led to general concerns related to the effects of scale. To investigate these concerns, with a particular focus on the contribution of the cladding to the global strength and stiffness of the structure (also referred to as the stressed skin effect), and the resulting demands placed on secondary components, this study presents the development of a numerical model for the accurate representation of the structural response of full single‐span portal frames. The model is validated herein in two ways; (i) through validation of each individual frame component against relevant physical experiments, and (ii) through validation of the full model against full scale frame tests. Finally, a preliminary parametric investigation is presented.