Column strength requirements in multi-storey seismic frames
DOI:
https://doi.org/10.5459/bnzsee.22.3.135-144Abstract
This paper examines factors affecting the strength requirements of columns in multi-storey frames responding to seismic ground motions.
The examination is carried out using an inelastic static analysis approach and the concept of an "equivalent condensed frame". In particular, the influence of higher modes and the effect of varying the pattern of beam flexural strength over the frame height are evaluated.
It is suggested that the current capacity design approach of the NZ Concrete Design Code overstates the importance of higher mode effects while neglecting the potentially more important influence of the beam flexural strength pattern that is provided for a frame.
Some tentative modifications to the current column design procedure are suggested for future evaluation under inelastic dynamic response conditions.
References
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Paulay, T, 1979, "Developments in the Design of Ductile Reinforced Concrete Frames", Bulletin of NZNSEE, Vol. 12. DOI: https://doi.org/10.5459/bnzsee.12.1.35-48
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Fenwick, R.C., Davidson, B.J., 1989, "Dynamic Behaviour of Multi-Storey Buildings", Report No. 463, University of Auckland, School of Engineering. (Note: Participation factors and mode shapes were obtained from the authors in private correspondence).
