Composite action of steel frames and precast concrete infill panels with corner connections – Part 2 : finite element analysis

When precast concrete infill panels are connected to steel frames at discrete locations, interaction at the structural interface is neither complete nor absent. The contribution of precast concrete infill panels to the lateral stiffness and strength of steel frames can be significant depending on the quality, quantity and location of the discrete interface connections. This paper presents preliminary finite element results of an investigation into the composite behaviour of a square steel frame with a precast concrete infill panel subject to lateral loading. Earlier, a full scale experiment was performed on a one-storey one-bay 3 by 3 m infilled frame structure which was horizontally loaded at the top and yielded a load displacement curve. The infill panel was connected at the corners to the ends of the top and bottom beams. This way the connection acts either in tension or compression. Experimental pullout tests on individual Frame-to-Panel-Connections, FPC4, allowed the load deflection characteristics to be established. This made it possible to model the experimental non-linear behaviour of the connection by multi-linear tensile and compression springs in the finite element model. The results from the finite element model of the infilled frame structure with FPC4 connections compares well with the experimentally obtained values for initial lateral stiffness, yielding level and ultimate strength. The proposed finite element model of the structure can be used for further parameter studies.