Equivalent Diagonal Strut Method for Masonry Walls in Pinned Connection and Multi-Bay Steel Frames

Document Type : Structural Earthquake Engineering


1 International Institute of Earthquake Engineering and Seismology (IIEES)

2 University of Minho


Equivalent compression strut is one of the most prevalent approaches recommended in seismic codes to simulate infill panels in the frames. The mechanical parameters of infilled frames, such as strength and stiffness, are controlled by material properties, thickness and width of equivalent strut. The strut width depends on the contact length between the infill and the frame. Previous studies have shown that the connection rigidity of the surrounding frame affects the contact length and consequently the response of infilled frame. Parametric finite element analyses have been carried out to investigate the influence of frame connection rigidity on the behavior of infill walls using ABAQUS environment. The finite elementmodels were verified based on the results of experimental data. It is shown that the stiffness and strength of infill panel in pinned connection steel frame are 0.9 and 0.8 times of those in rigid connection frame, respectively. The results of parametric finite element analyses were validated using equivalent strut method. Moreover, it is shown that the equivalent diagonal struts in multi-bay frame have the same properties of strut in one-bay frames for both rigid and pinned connections ones.


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