COMPUTATIONAL SIMULATION OF TIME-EFFECT ON BEARING CAPACITY OF JACKED PILE
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摘要: 静压桩承载力的提高归因于桩周土的固结、触变恢复和土壳效应,其中固结作用是主要的。从超静孔隙水压力消散和有效应力的增加两方面着手,对桩承载力的增长规律进行分析,利用球孔扩张理论、源-源假设理论以及Henkel公式,推导出沉桩后桩周土应力增量的表达式,并通过求解超静孔隙水压力与时间的关系式,得出任意时刻超静孔隙水压力的表达式,进而提出饱和土中静压桩承载力时效性的模拟计算式。通过与试验结果对比发现,预测结果随休止期的延长而提高。Abstract: The improvement of bearing capacity dependeds on three aspects of soil consolidation,disturb-restore property and shell-effect.The effect of soil consolidation is most important,so the law of time-effect is studied from this aspects of pore pressure dissipation and effective stress increase.By using the theory of spherical cavity expansion,imaging method and formula Henkel,the expression of stress increase after installation is deduced and the expression of pore pressure at any time by computing the equation of pore pressure and time,then stimulation computation method of bearing time-effect in saturated soil is presented.Comparing with test results,it is showed that the calculation is receivable.
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Key words:
- jacked pile /
- time effect /
- pore pressure /
- dissipation
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