Pore Water Pressure and Liquefaction in Saturated Sand Bed Induced by Tsunami
Pore Water Pressure and Liquefaction in Saturated Sand Bed Induced by Tsunami
复制标题
海啸引起的饱和砂层孔隙水压力与液化
DOI：
10.11408/jsidre.82.113
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
T. Kawabata
中科院分区：
文献类型：
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作者：
Y. Sawada;Michio Miyake;H. Sumida;T. Kawabata
本文从理论和实验两个方面讨论了海啸作用下饱和砂土的孔隙水压力和液化问题。提出了基于达西定律的控制方程，并通过离心模型试验验证了控制方程的适用性。此外，数值模拟进行了一维，2011年3月11日（MLIT日本）的GPS浮标观测海平面作为输入数据，以评估孔隙压力和液化的实际海啸。此外，参数研究假设透水层为粉土，渗透性对液化的影响进行了讨论。实验结果表明，海啸使有效应力降低。结果表明，计算值与实测值吻合较好，所建立的液化势控制方程适用于评价液化势。此外，它表明，液化可能会发生由于实际的海啸，即使渗透层是比较好的排水，如桑迪土。超孔隙水压力比随浅层渗透率的减小而增大，其影响范围可达地下4m。
Pore water pressure and liquefaction in a saturated sand bed induced by tsunami are theoretically and experimentally discussed. A governing equation on the basis of the Darcy's law is presented, and a centrifugal model test is carried out to verify the applicability of the governing equation. In addition, numerical simulations are performed in one-dimension, giving observed sea levels by GPS buoys on 11 March, 2011 (MLIT Japan) as the input data, in order to evaluate pore pressure and liquefaction by the actual tsunami. Moreover, parametric studies are performed assuming a permeable layer as silt, and the influence of permeability on liquefaction is discussed. Experimental results show that the effective stress decreases due to tsunami. It is evident that the calculated values are in good agreement with the observed values, and the governing equation is applicable to evaluate the liquefaction potential. In addition, it is revealed that liquefaction can occur due to the actual tsunami even if the permeable layer is comparatively good drainage like sandy soil. It is also clear that the excess pore water pressure ratio increases with the decrease of permeability at the shallow depth, and the influence ranges up to the depth of 4 m below the ground.