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Seismic Analysis of an Offshore Structure Supported on Pile Foundations.
Liou, D. D. N.; Penzien, J.
Standard Oil Co. of California, San Francisco.; National Science Foundation, Washington, D.C., November 1977, 116 p.
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This report presents an analytical study of the seismic response characteristics of an offshore structure supported on pile foundations. To allow the basic modeling of the structure-foundation system, a simple mathematical model of pile foundation based on the three-dimensional theory of elasticity is developed. The earthquake surface ground motion is prescribed in the time domain, the solution of the system is carried out in the frequency domain, and the desired response quantities are transformed back to the time domain. Foundation-structure interaction effects are examined by comparing response quantities obtained for models with and without foundation flexibility. The interaction effects are found to be quite significant.
Elastic theory; Offshore structures; Equations of motion; Mathematical models; Earth movements; Ground motion; Earthquake engineering; Soil dynamics; Pile foundations; Seismic response; Foundation structure interactions; Earthquakes