Experimental and Numerical Studies of the Excess Pore Pressure Field Surrounding an Advancing Spudcan Footing
Experimental and Numerical Studies of the Excess Pore Pressure Field Surrounding an Advancing Spudcan Footing
复制标题
推进桩基周围超孔隙压力场的实验和数值研究
DOI：
10.1115/1.4038344
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Liu Yong
中科院分区：
文献类型：
--
作者：
Yi Jiang Tao;Li Yu Ping;Li Yi Wei;Yang Yu;Liu Yong
桩基的快速顶进过程往往会在桩底下方产生大量的过剩孔压。因此，对超孔压浓度的深入了解对于了解桩基的短期和长期力学行为都具有重要意义。到目前为止，这方面的信息还很匮乏。本文提出了一项全面的研究，以探索前进中的泥盆周围的超孔压场的模式和大小。包括离心机试验和有效应力大变形有限元分析(LDFEA)，前者主要用于基准后者，后者提供了一个完整的超孔压信息库。在泥盆底下方发现了球状的超孔压集中区。压力球的大小及其内部的超孔压大小与贯入深度和土性密切相关。参数研究的结果导致了一种简单而实用的方法来估计土体中的土层超孔压，而不需要进行复杂的计算。提供了必要的图表，以方便使用。预计这种方法的开发可以帮助实践工程师快速而粗略地估计自升式贯入过程中产生的超孔压，并为其短期和长期影响做好准备。
The rapid jack-in process of spudcan footing tends to generate substantial build-up of excess pore pressure below the spudcan underside. An intimate knowledge of the excess pore pressure concentration is thus of significance for understanding both the short-term and long-term mechanical behavior of spudcan. As yet there is a dearth of information in this area. This paper presents a comprehensive research to explore the pattern and magnitude of the excess pore pressure field surrounding an advancing spudcan. Both centrifuge experiments and effective-stress large deformation finite element analyses (LDFEAs) were involved, while the former served mainly to benchmark the latter and the latter provided a complete information database of the excess pore pressure. The bulb-shaped excess pore pressure concentration zone was identified below the spudcan underside. Sizes of pressure bulbs as well as the magnitudes of excess pore pressures inside them bore close relationship to the penetration depths and soil's properties. The results of parametric study led to the development of a simple yet useful approach to estimate the spudcan-penetration-induced excess pore pressure in soil without carrying out the complicated computation. Necessary charts and tables were provided to facilitate its usage. It is expected that the development of such an approach can aid the practicing engineer to obtain a quick and rough estimate of excess pore pressure generated in the midst of the jack-up spudcan penetration and prepare for its short-term and long-term implications.