Axisymmetric Consolidation in Unsaturated Soil Deposit Subjected to Time-Dependent Loadings
Publication: International Journal of Geomechanics
Volume 17, Issue 2
Abstract
This paper presents an analytical solution to predict the axisymmetric consolidation in unsaturated soil deposits subjected to different time-dependent loadings. The mathematical procedure uses the separation of variables and Laplace transformation methods to obtain the final solution. A set of polar governing equations of flow are obtained and presented under the partial differential equations (PDEs), and then the variable separation technique is used to alter the PDEs to ordinary differential equations (ODEs) consisting of distinctive variables. Fourier Bessel and sine series are used to present functions of radial and vertical flows, respectively, and the Laplace transformation is used to obtain a function of time. Four primary time-dependent loading functions, including ramping, asymptotic, sinusoid, and damped sine wave, are mathematically simulated and incorporated into the proposed solutions. This study investigates changes in excess pore-air and pore-water pressures as well as consolidation settlement against the air-to-water permeability ratio and various loading parameters. Moreover, changes in suction and net stress induced by ramped and asymptotic loadings are also presented in the worked examples.
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Published In
International Journal of Geomechanics
Volume 17 • Issue 2 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Oct 19, 2015
Accepted: Feb 26, 2016
Published online: May 10, 2016
Discussion open until: Oct 10, 2016
Published in print: Feb 1, 2017
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