Simplified discrete systems for dynamic analysis of structures on footings and piles |
| |
| Institution: | 1. Department of Engineering, University of Patras, Patras 26500, Greece;2. Department of Civil Engineering, University of Patras, Patras 26500, Greece;3. University of California at Los Angeles, Los Angeles, CA 90095-1593, USA;4. Department of Civil Engineering, University of Patras, Patras 26500, Greece;1. School of Civil Engineering, College of Engineering, University of Tehran, P.O.Box 11165-4563, Tehran, Iran;2. Department of Civil Engineering, Mazandaran University of Science and Technology, Babol, Iran;1. Consulting Engineer, GR-58100 Giannitsa, Greece;2. School of Science and Technology, Hellenic Open University, GR-26335 Patras, Greece;3. Department of Civil Engineering, University of Patras, GR-26500 Patras, Greece;4. Office of Theoretical and Applied Mechanics, Academy of Athens, GR-11527 Athens, Greece;5. Institute of Soil Mechanics and Rock Mechanics, K.I.T., D-76128 Karlsruhe, Germany;1. Department of Civil Engineering, The University of Nottingham, UK;2. Department of Civil & Structural Engineering, The University of Sheffield, UK |
| |
| Abstract: | A simplified discrete system in the form of a simple oscillator is developed to simulate the dynamic behavior of a structure founded through footings or piles on compliant ground, under harmonic excitation. Exact analytical expressions for the fundamental natural period and the corresponding damping coefficients of the above system are derived, as function of geometry and the frequency-dependent foundation impedances. In an effort to quantify the coupling between swaying and rocking oscillations in embedded foundations such as piles, the reference system is translated from the footing–soil interface to the depth where the resultant soil reaction is applied, to ensure a diagonal impedance matrix. The resulting eccentricity is a measure of the coupling effect between the two oscillation modes. The amounts of radiation damping generated from a single pile and a surface footing are evaluated. In order to compare the damping of a structure on a surface footing and a pile, the notion of static and geometric equivalence is introduced. It is shown that a pile may generate significantly higher radiation damping than an equivalent footing, thus acting as an elementary protective system against seismic action. |
| |
| Keywords: | Soil–structure interaction Piles Footings Natural period Radiation damping Foundation impedance |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
