Dynamic tests on laminated rubber bearings
DOI:
https://doi.org/10.5459/bnzsee.10.3.143-150Abstract
Simulated dynamic tests in shear on laminated rubber bearings are described. The purpose of the tests was to check the performance of the bearings when used as mounts for base isolating buildings against earthquake attack.
Over 1,000 cycles were applied to the bearings, mostly at 50% shear strain at a frequency in the range 0.2 to 0.9Hz. Values of damping were checked by carrying out separate torsional oscillation tests.
It is concluded that the bearings are suitable for use in the dynamic mode for the purpose of achieving base isolation in earthquake resistant buildings. Damping is likely to be 2 to 3% of critical. Possibly greater values occur at faster speeds and under cold conditions. The use of separate lead or steel damping elements to prevent the build-up of damaging horizontal oscillations is considered necessary.
References
Crockett, J.H.A., Recent Developments in Spring Insulated Buildings, N.R.P.R.A., 3rd Rubber in Engineering Conference 1973.
Lindley, P.B., Designing with Rubber, N.R.P.R.A. 3rd Rubber in Engineering Conference 1973.
Delfosse, G. C,, The Gapec System: a New Highly Effective Aseismic System. Proceedings Sixth World Conference on Earthquake Engineering, New Delhi, 1977.
Skinner, R. I., Beck, J. L., and Bycroft, G. N. A Practical System for Isolating Structures from Earthquake Attack. Earthquake Engineering and Structural Dynamics, 3, p. 297-309, 1975. DOI: https://doi.org/10.1002/eqe.4290030308
Robinson, W. H., and Greenbank, L. R., An Extrusion Energy Absorber Suitable for the Protection of Structures During an Earthquake. Earthquake Engineering and Structural Dynamics, 4, p.251-259, 1976. DOI: https://doi.org/10.1002/eqe.4290040306
Robinson, W. H., and Tucker, A. G., A Lead-Rubber Shear Damper. Bulletin of the N.Z. National Society for Earthquake Engineering, Vol. 10, No. 3 September, 1977. DOI: https://doi.org/10.5459/bnzsee.10.3.151-153
Skinner, R. I., Heine, A. J. and Tyler, R. G., Hysteretic Dampers to Provide Structures with Increased Earthquake Resistance. Sixth World Conference on Earthquake Engineering, New Delhi, January, 1977.
Tyler, R. G., and Skinner, R. I., Testing of Dampers for the Base Isolation of a Proposed 4-Storey Building Against Earthquake Attack. Sixth Australasian Conference on the Mechanics of Structures and Materials, University of Canterbury, Christchurch, New Zealand, August 1977.
Naughton, W. J. S., Rubber Must be Used Correctly. Proceedings: Rubber in Engineering Conference: Natural Rubber Development Board, London 1956.
Lindley, P. B., Engineering Design with Natural Rubber. N.R. Technical Bulletin, Malaysian Rubber Producers’ Research Association, London.
