iConsol.js: JavaScript Implicit Finite-Difference Code for Nonlinear Consolidation and Secondary Compression
Publication: International Journal of Geomechanics
Volume 17, Issue 6
Abstract
In this study, an implicit finite-difference code for nonlinear consolidation and secondary compression was developed and implemented in a publicly available JavaScript Web application. The rate of secondary compression was defined based on the distance in e-log10() space between a current point and a corresponding point on a reference secondary compression line (RSCL). Modeling secondary compression in this manner enables simultaneous occurrence of primary consolidation and secondary compression. The finite-difference code was first verified by comparison with three benchmarks. The influence of secondary compression on settlement versus time was then studied and found to be important for thick and/or low-permeability layers for which primary consolidation requires significant time. Overconsolidated soil was observed to result in an apparent increase in Cα with time, which was also observed in experimental data. Finally, secondary compression was found to be capable of generating excess pore pressure in soils with impeded drainage boundaries.
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Acknowledgments
The author thanks his colleagues Jonathan Stewart and Ali Shafiee for their input on the details of the consolidation code. The author thanks Mandro Eslami for helping to set up the isotropic consolidation test on Sherman Island peat. Last, the author thanks the students in his advanced soil mechanics graduate course, who served as guinea pigs for the code and helped him work out many of the bugs. This work was performed as part of a research study funded by the California Department of Water Resources under Contract 4600010406. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the California Department of Water Resources.
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© 2016 American Society of Civil Engineers.
History
Received: Mar 24, 2016
Accepted: Sep 20, 2016
Published online: Nov 21, 2016
Discussion open until: Apr 21, 2017
Published in print: Jun 1, 2017
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