Location

San Diego, California

Session Start Date

3-26-2001

Session End Date

3-31-2001

Keywords and Phrases

Pile, Stiffness, Damping, Impedance, Inhomogeneity, Winkler, Analysis

Abstract

The flexural stiffness and damping (dynamic impedance) of a single vertical pile in an inhomogeneous soil deposit with continuously increasing stiffness with depth, is studied. An analytical formulation based on the Beam-on-Dynamic-Winkler-Foundation (BDWF) model is implemented. The model is used in conjunction with a virtual work approximation and pertinent shape functions for the deflected shape of a long flexible pile, which are analogous to those used in finite-element formulations. Explicit closed-form solutions are derived for: (1) the dynamic pile stiffness; and (2) the damping coefficient at the pile head. Both swaying and rocking vibrations are considered and all associated impedance coefficients (swaying, rocking, and cross swaying-rocking) are determined. Results from the method are found to be in good agreement with earlier solutions, while new results are developed. The errors resulting from the use of an “equivalent” homogeneous profile with average properties are discussed.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Meeting Name

Fourth Conference

Publisher

University of Missouri--Rolla

Publication Date

3-26-2001

Document Version

Final Version

Rights

© 2001 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

Share

COinS
 
Mar 26th, 12:00 AM Mar 31st, 12:00 AM

Lateral Impedance of Single Piles in Inhomogeneous Soil

San Diego, California

The flexural stiffness and damping (dynamic impedance) of a single vertical pile in an inhomogeneous soil deposit with continuously increasing stiffness with depth, is studied. An analytical formulation based on the Beam-on-Dynamic-Winkler-Foundation (BDWF) model is implemented. The model is used in conjunction with a virtual work approximation and pertinent shape functions for the deflected shape of a long flexible pile, which are analogous to those used in finite-element formulations. Explicit closed-form solutions are derived for: (1) the dynamic pile stiffness; and (2) the damping coefficient at the pile head. Both swaying and rocking vibrations are considered and all associated impedance coefficients (swaying, rocking, and cross swaying-rocking) are determined. Results from the method are found to be in good agreement with earlier solutions, while new results are developed. The errors resulting from the use of an “equivalent” homogeneous profile with average properties are discussed.