Analytical and Numerical Modeling of Soft Soil Stabilized by Prefabricated Vertical Drains Incorporating Vacuum Preloading
Publication: International Journal of Geomechanics
Volume 5, Issue 2
Abstract
This paper describes the analytical formulation of a modified consolidation theory incorporating vacuum pressure, and numerical modeling of soft clay stabilized by prefabricated vertical drains, with a linearly distributed (trapezoidal) vacuum pressure for both axisymmetric and plane strain conditions. The effects of the magnitude and distribution of vacuum pressure on soft clay consolidation are examined through average time-dependent excess pore pressure and consolidation settlement analyses. The plane strain analysis was executed by transforming the actual vertical drains into a system of equivalent parallel drain walls by adjusting the coefficient of permeability of the soil and the applied vacuum pressure. The converted parameters are incorporated in the finite element code ABAQUS, employing the modified Cam-clay theory. Numerical analysis is conducted to study the performance of a full-scale test embankment constructed on soft Bangkok clay. The performance of this selected embankment is predicted on the basis of four different vacuum pressure distributions. The predictions are compared with the available field data. The assumption of distributing the vacuum pressure as a constant over the soil surface and varying it linearly along the drains seems justified in relation to the field data.
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Information
Published In
International Journal of Geomechanics
Volume 5 • Issue 2 • June 2005
Pages: 114 - 124
Copyright
© 2005 ASCE.
History
Received: Feb 9, 2004
Accepted: Jul 22, 2004
Published online: Jun 1, 2005
Published in print: Jun 2005
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