Floor Diaphragm In-Plane Modelling Using Elastic Truss Elements

Abstract:

Different methods to model building floor diaphragm in-plane stiffness with truss elements are compared to identify the method most suitable for analysis in design. The methods considered include (i) an elastic diagonal truss element model, and (ii) an elastic diamond truss element model. The truss elements were placed in square blocks and are compared with FEM in terms of stiffness and capturing beam axial forces. It was found that diagonal model transferred some part of diaphragm force directly to the column. The diamond framework superior because it was less sensitive to mesh size, gives a more accurate stiffness with a lower number of elements and a more accurate beam axial force. Furthermore, it better provides information in a better format for design.

• Periodical: Key Engineering Materials (Volume 763)
• Pages: 549-556
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.763.549
• Online since: February 2018
• Authors: Saeid Alizadeh, Gregory A. MacRae*, Des Bull, George Charles Clifton
• Keywords: Beam Axial Force, Diaphragm Modelling, Strut, Tie, Truss Method

References

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