A Simplified Method for One-Dimensional Consolidation of Unsaturated Soils
Publication: International Journal of Geomechanics
Volume 23, Issue 1
Abstract
A simplified analytical method is proposed for one-dimensional unsaturated soil consolidation theory. First, in the one-dimensional compression test of unsaturated soil, the effective stress principle of saturated soil under compression is introduced to replace the constitutive relation expressed by the state of double stress in Fredlund’s theory. Based on this, the governing equations composed of two bi-variable partial differential equations are obtained. In the process of derivation, the dissipation law of pore pressure during the consolidation process is analyzed and the theoretical rationality is demonstrated. When solving the system of equations, considering that the initial excess pore water and the gas pressure are caused by instantaneous loading, Hilf’s theory is improved to calculate the change of pore pressure. This improvement is more in line with the actual situation and simplifies the approximate calculation method to obtain the analytical solution when the coupling effect of water and gas is considered. This method is verified by comparing with Terzaghi’s theory and Fredlund’s theory. It is shown that the solution of Terzaghi’s theory is a special case of this method for saturated soil, and the results of the dissipative process obtained with the method is close to Fredlund’s theory.
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Acknowledgments
The study was supported by the Program for Science and Technology Innovation Team in Colleges of Hubei Province (CN) under Grant No. T201823, the National Natural Science Foundation of China under Grant No. 51478201, the Natural Science Foundation of Hubei Province (CN) under Grant No. 2012FKC14201, the Scientific Research Foundation of Education Department of Hubei Province (CN) under Grant No. D20134401, the Natural Science Foundation of Hubei Polytechnic University under Grant No. 13xjz03A, and the Innovation Foundation in Youth Team of Hubei Polytechnic University under Grant No. Y0008. Their financial support is gratefully acknowledged.
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Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 23 • Issue 1 • January 2023
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Oct 23, 2021
Accepted: Jul 13, 2022
Published online: Oct 31, 2022
Published in print: Jan 1, 2023
Discussion open until: Mar 31, 2023
ASCE Technical Topics:
- Analysis (by type)
- Consolidated soils
- Continuum mechanics
- Dimensional analysis
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Geomechanics
- Geotechnical engineering
- Pore pressure
- Pressure (type)
- Saturated soils
- Soft soils
- Soil analysis
- Soil compression
- Soil dynamics
- Soil mechanics
- Soil properties
- Soil stress
- Soils (by type)
- Solid mechanics
- Unsaturated soils
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Cited by
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