This paper describes a numerical model for predicting the pile foundation conditions with negative friction and soil consolidation. The geotechnical finite element software Plaxis was used to create the numerical model and soil replacement method to simulate initial soil state before acceleration of the centrifuge. Then, the development of negative friction was simulated, and the results are quite accurate. The predicted soil settlement error after consolidation is within 6.8% of the test data, the pile settling error is within 34.7% and the piling force error is within 18.3%. In addition, the excess pore pressure and relative maximum axial piling force are consistent with centrifuge test data for various consolidation times and axial force is approximately linearly related with the square root of time. This model provides reference data for calculating single pile foundations with negative friction and soil consolidation.
Key words
single pile /
negative friction /
soil consolidation /
numerical model /
centrifuge test
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References
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