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Mode superposition in multi-degree of freedom systems using earthquake response spectrum data

Merchant, H. C. and Hudson, D. E. (1962) Mode superposition in multi-degree of freedom systems using earthquake response spectrum data. Bulletin of the Seismological Society of America, 52 (2). pp. 405-416. ISSN 0037-1106.

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Dynamic responses of a series of typical three-degree of freedom structures to strong-motion earthquake excitation were calculated by analog computer techniques and were compared with approximate responses obtained by a superposition of individual modes derived from response spectrum curves. The results indicate that a suitably weighted average of the sum of the absolute values of the individual modes and the square root of the sum of the squares of the modes will give a practical design criterion for the base shear forces in multi-story buildings. For critical designs, this weighted average reduces to the absolute sum of the modes, which is found to be close to the true value for a significantly high proportion of typical earthquake-structure combinations.

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Additional Information:Copyright © 1962, by the Seismological Society of America. Manuscript received September 8. 1961. Thanks are expressed to Professor G. W. Housner and T. K. Caughey of the Division of Engineering, California Institute of Technology, for their contributions to this investigation.
Issue or Number:2
Record Number:CaltechAUTHORS:20140801-113026550
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:47804
Deposited By: George Porter
Deposited On:01 Aug 2014 19:59
Last Modified:03 Oct 2019 06:57

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