ISSN: 1304-7191 | E-ISSN: 1304-7205
Effects of Infill Walls on Free Vibration Characteristics of Multi-Storey Frames Using Dynamic Stiffness Method
1Dokuz Eylul University, Department of Civil Engineering, Buca-İZMİR
Sigma J Eng Nat Sci 2019; 37(3): 885-902
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Abstract

This study aims to obtain exact natural frequencies and mode shapes of infilled multi-storey frames using single variable shear deformation theory (SVSDT) which considers parabolic transverse shear stress distribution across the cross-section. The effects of infill walls on free vibration characteristics are investigated for different frame models such as one storey infilled, soft storey and fully infilled. The infill walls are modeled using equivalent diagonal strut approach. Natural frequencies are calculated via dynamic stiffness formulations for different wall thickness values. The results of SVSDT are tabulated with Euler-Bernoulli beam theory (EBT) and Timoshenko beam theory (TBT) results. Additionally, finite element solutions are presented to verify the natural frequencies that obtained from dynamic stiffness formulations. The results show that SVSDT can be used effectively for free vibration analysis of infilled frame structures by using dynamic stiffness formulations. The numerical analyses show that the effects of shear deformation and rotation inertia become observable for higher modes of infilled frame structures. It is seen from the results that ignoring effects of infill walls may cause significant errors on calculation of natural frequencies of frames.