Department of Structural Design and Construction Technology, Eindhoven University of Technology

Although the contribution of infill walls to resist gravity and lateral loads is still commonly unaccounted for in structural design, there is ample experimental and numerical evidence that the behaviour of infilled frames significantly varies from that of frames or walls considered separately. Accounting for the contribution of infill walls can result in greater structural efficiency, reduced risks to damage and enhanced aesthetics. In Europe, calcium silicate element (CASIEL) walls, as a case in point, are increasingly employed as partitions and external claddings in buildings. This paper provides an overview of global and fundamental models that have been formulated by various researchers to analyse infilled frames. These methods are applied to CASIEL-infilled steel frames. Analytical results are compared with numerical results and experimental results from ten large-scale tests. In view of the large number of indeterminate factors at the frame-infill contact areas that affect the behaviour, simplified expressions for approximating the stiffness and cracking loads of the infilled frames are proposed. These expressions are based on an equivalent diagonal strut approach.