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| Numerical simulation of electro-osmosis consolidation considering variation of electrical conductivity |
| WU Hui1, 2, HU Li-ming1, 2 |
| 1. State Key Laboratory of Hydro-Science and Engineering, Beijing 100084, China; 2. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China |
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Abstract Electro-osmosis is an effective method for soft ground improvement. During the electro-osmosis process, the electrical conductivity of soil is different at different positions and changes with time. In order to predict the behaviour of soil, a 1D axisymmetric electro-osmosis experiment is carried out to study the variation of the electrical conductivity during the electro-osmosis process. The finite element method software is developed to simulate the electro-osmosis process in which the seepage field is coupled with the stress and strain fields with relationship of the electric conductivity and the void ratio incorporated. The results indicate that the voltage and voltage gradient change with time. The results of the numerical model which considers the variation of electric conductivity agree better with the experimental ones than those of the numerical model which neglects the variation of electric conductivity. During the electro-osmosis process, the settlement at the anode is the largest. However, in the experiment, the largest settlement is observed between the anode and the cathode since the friction between the soil and the test devices limits the settlement at the anode.
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Received: 26 April 2012
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