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Title: The Frequency and Damping of Soil-Structure Systems with Embedded Foundation

Abstract

The effect of foundation embedment on fundamental period and damping of buildings has been the title of several researches in three past decades. A review of the literature reveals some discrepancies between proposed formulations for dynamic characteristics of soil-embedded foundation-structure systems that raise the necessity of more investigation on this issue. Here, first a set of approximate polynomial equations for soil impedances, based on numerical data calculated from well known cone models, are presented. Then a simplified approach is suggested to calculate period and damping of the whole system considering soil medium as a viscoelastic half space. The procedure includes both material and radiation damping while frequency dependency of soil impedance functions is not ignored. Results show that soil-structure interaction can highly affect dynamic properties of system. Finally the results are compared with one of the commonly referred researches.

Authors:
; ;  [1]
  1. Department of Civil Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
21149035
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1020; Journal Issue: 1; Conference: 2008 seismic engineering conference: Commemorating the 1908 Messina and Reggio Calabria earthquake, Reggio Calabria (Italy), 8-11 Jul 2008; Other Information: DOI: 10.1063/1.2963895; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; BUILDINGS; DAMPING; EARTHQUAKES; FOUNDATIONS; HYDROLOGY; MECHANICAL IMPEDANCE; POLYNOMIALS; REVIEWS; SEISMOLOGY; SOIL-STRUCTURE INTERACTIONS; SOILS

Citation Formats

Ghannad, M. Ali, Rahmani, Mohammad T., and Jahankhah, Hossein. The Frequency and Damping of Soil-Structure Systems with Embedded Foundation. United States: N. p., 2008. Web. doi:10.1063/1.2963895.
Ghannad, M. Ali, Rahmani, Mohammad T., & Jahankhah, Hossein. The Frequency and Damping of Soil-Structure Systems with Embedded Foundation. United States. doi:10.1063/1.2963895.
Ghannad, M. Ali, Rahmani, Mohammad T., and Jahankhah, Hossein. Tue . "The Frequency and Damping of Soil-Structure Systems with Embedded Foundation". United States. doi:10.1063/1.2963895.
@article{osti_21149035,
title = {The Frequency and Damping of Soil-Structure Systems with Embedded Foundation},
author = {Ghannad, M. Ali and Rahmani, Mohammad T. and Jahankhah, Hossein},
abstractNote = {The effect of foundation embedment on fundamental period and damping of buildings has been the title of several researches in three past decades. A review of the literature reveals some discrepancies between proposed formulations for dynamic characteristics of soil-embedded foundation-structure systems that raise the necessity of more investigation on this issue. Here, first a set of approximate polynomial equations for soil impedances, based on numerical data calculated from well known cone models, are presented. Then a simplified approach is suggested to calculate period and damping of the whole system considering soil medium as a viscoelastic half space. The procedure includes both material and radiation damping while frequency dependency of soil impedance functions is not ignored. Results show that soil-structure interaction can highly affect dynamic properties of system. Finally the results are compared with one of the commonly referred researches.},
doi = {10.1063/1.2963895},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1020,
place = {United States},
year = {Tue Jul 08 00:00:00 EDT 2008},
month = {Tue Jul 08 00:00:00 EDT 2008}
}
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