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- 2015
考虑固结过程的单桩负摩擦数值模型
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Abstract:
该文旨在建立考虑地基土固结过程的桩基负摩擦计算模型。基于岩土工程有限元软件Plaxis建立有限元模型, 并使用换土法模拟离心机加速前土的欠固结状态, 进而模拟试验负摩擦发展过程。计算结果表明: 该模型计算精度较高, 固结完成时远端土的沉降计算误差为6.8%, 桩基沉降和轴力的计算误差分别为34.7%和18.3%; 此外, 不同固结时刻下的超静孔压以及桩基最大轴力相对值与离心机试验数据吻合, 且桩基轴力均近似与时间的平方根成线性关系。该模型可为考虑地基图固结的桩基负摩擦问题的计算提供参考。
Abstract：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.
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