Steady state vibration tests of a six-storey reinforced concrete building

  • A. M. Reay Hardie and Anderson, Christchurch, New Zealand
  • R. Shepherd University of Canterbury, Christchurch, New Zealand

Abstract

Five modes of vibration of a six-storey reinforced concrete building were excited by steady-state resonance testing. Good correlation between predicted and measured frequencies was obtained.

In the lateral translation tests, two translation modes and the vibration of the roof as a free-free beam were excited. Damping measured in the fundamental mode was 4.1% critical and the average contribution of foundation compliance to the top-storey deflection was 32%. Damping in the second translation mode was 6.6% and of the free-free beam vibration, 3.6%.

The first torsional mode of the building was excited, and for an eight-fold increase in excitation force, the natural frequency reduced by 1.2%, indicating a slight degree of non-linearity in the response. Damping in this mode was 6.9% , no change being noted for the eight-fold force increase.

In the longitudinal direction, two modes were excited, the first torsional mode and the first longitudinal translation mode. Properties of the former were similar to those determined from the torsional response test. Damping in the translation mode was 10.1% and the foundation compliance contributed 24% of the top-storey deflection.

References

Basic Design Loads. N.Z.S.S. 1900 Chapter 8, N.Z. Standards Institute 1965.

Shepherd, R. and Reay, A, M0 Some Apparatus for the Small Amplitude Dynamic Testing of Multistorey Buildings, Strain, Journal of the British Society Vol. 3 – No. 4. October 1967.

Shepherd, R. Determination of Seismic Design Loads in a Framed Structure New Zealand Engineering, 1967, 22(2), 56-61.

Shepherd, R. and Donald, R.A.H. Foundation Deformation Effects in Structural Dynamic Analysis Proceedings, Fifth Australia - New Zealand Soil Mechanics Conference, Auckland, 1967, 205-212.

Reay, A. M. Dynamic Characteristics of Civil Engineering Structures. Unpublished Ph.D. The sis. University of Canterbury 1970.

Den Hartog, J.P. Mechanical Vibrations. McGraw Hill Book Co. Inc. 1947.

Nielson, N. N. Dynamic Response of Multi-storey Buildings. Earthquake Engineering Research Laboratory, California Institute of Technology, Pasadena, California 1964 .

Muto, K. Seismic Analysis of Reinforced Concrete Building. Shokoku-Sha Publishing Company, Tokyo, Japan 1965.

Barkan, D. P. Dynamics of Bases and Foundations. McGraw-Hill, New York, 1962.

Published
1971-03-31
How to Cite
Reay, A. M., & Shepherd, R. (1971). Steady state vibration tests of a six-storey reinforced concrete building. Bulletin of the New Zealand Society for Earthquake Engineering, 4(1), 94-107. https://doi.org/10.5459/bnzsee.4.1.94-107
Section
Articles