Micromechanics Study on Liquefaction-Induced Lateral Flow and Soil-Pile Interaction

液化诱发侧流及土-桩相互作用的微观力学研究

• 批准号: 15360249
• 负责人: YAMADA Yasuo
• 金额: $ 9.41万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15360249/
• 关键词: Liquefaction; Lateral ground flow; Visualization technique; PIV (particle image Velocimetry); LAT (Laser-Aided tomography); DEM (Discrete Element Method); SPH (Smoothed Particle Hydrodynamics); Micromechanics; 杭基礎; 微視力学; 構成則; 流動; 個別要素法

Lateral spreading induced by seismic liquefaction causes the ground to experience large displacement and shear strains, which in turn damage pile foundations due to the drag force. There are two difficulties in simulating this problem ; the evaluation of constitutive model for liquefied soil and the choice of adequate simulation tool suitable for such large deformation problem. The objective of this study is to find a way for these difficulties from a micromechanical standpoint.Firstly, we developed some experimental techniques using high-speed camera and PIV (Particle Image Velocimetry). PIV is a powerful tool to detect a velocity field of various experiments from sequential digital images. We performed two types of experiments : one is a shaking table test of Toyoura sand to observe a surface of small-sized ground model, and the other is a kind of permeability test to keep arbitrary liquefaction state by tuning a fluid injection speed from the bottom of the specimen. In both experime … More nts, a cylindrical pipe is installed to measure the drag force acting on it due to the relative displacement between the specimen and the pipe. It was found that the liquefied soil has both properties as a solid (detected by a stick-slip motion between the soil and the pile) and as a viscous fluid (characterized by the rate dependent response).Further investigation was made by DEM (Discrete Element Method). DEM is a simulation method to compute each solid grains based on Newton's second law of motion, and the interaction between grains is simply modeled by a spring-dashpot-slider system. A series of constant-volume simple shear simulations provided us to observe essential micro-mechanisms up to and after liquefaction. In particular, the re-solidification of liquefied soil was also successfully simulated, which is quite important factor to predict the lateral flow displacement due to liquefaction.Based on the above information, we proposed a constitutive model of granular assembly based on micromechanics, which can be well applied up to shear failure of the assembly.Finally, we studied SPH (Smoothed Particle Hydrodynamics), a particle-based simulation method for continuum, which can be applied both in solid and fluid. It was found that the pile-liquefied soil interaction including the re-solidification regime was successfully simulated by SPH. Less

地震液化引起的散布会导致大量的位移和剪切菌株，这是由于拖拉而造成的。首先，我们使用高速相机和PIV开发了某种实验性技术（粒子图像速度计）。小型地面模型，另一个是一种通过从样品的底部调整速度来保持任意液化状态的渗透性测试。样品和管道（以率依赖响应为特征）。通过DEM进行（离散元素方法）。由弹簧式扫描系统建模。在上述信息上，我们提出了一个基于E的颗粒组件模型（平滑粒子流体动力学），这是一种基于粒子的仿真方法，可用于固体和流体

项目成果

A 2D Smoothed Particle Hydrodynamics method for liquefaction induced lateral spreading analysis

• DOI: 10.2208/journalam.8.591
• 发表时间: 2005-08
• 期刊: Journal of Applied Mechanics
• 作者: M. Naili;T. Matsushima;Yasuo Yamada

LAT-PIV Visualization technique and Application to solid particle-fluid interaction

LAT-PIV可视化技术及其在固粒-流体相互作用中的应用

• 发表时间: 2005
• 期刊: Journal of Applied Mechanics, JSCE (in Japanese) Vol.8
• 作者: Hidetaka Saomoto;Takashi Matsushima;Yasuo Yamada
• 通讯作者: Yasuo Yamada

竿本 英貴: "デジタル画像を利用した粒子-流体系内部の速度場計測"土木学会第58回年次学術講演会. (2003)

Hidetaka Kanomoto：“使用数字图像测量粒子流体系统内的速度场”第 58 届日本土木工程师学会学术年会（2003 年）。

SPH-DEM手法の開発とボイリング現象への適用

SPH-DEM方法的发展及其在沸腾现象中的应用

• 发表时间: 2005
• 期刊: 第40回地盤工学研究発表会講演概要集 (CD-ROM)
• 作者: Naili;M.;Matsushima;T.;Yamada;Y.;Takashi Matushima;Mounir NAILI;竿本英貴;Mounir NAM;竿本英貴
• 通讯作者: 竿本英貴

ボイリング時における粒子-流体系内部の可視化と速度場計測

沸腾过程中颗粒-流体系统内部的可视化和速度场测量

• 发表时间: 2004
• 期刊: 第39回地盤工学研究発表会講演概要集
• 作者: Naili;M.;Matsushima;T.;Yamada;Y.;Takashi Matushima;Mounir NAILI;竿本英貴;Mounir NAM;竿本英貴;Mounir NAILI;Mounir NAILI;竿本英貴;Mounir NAILI;松島亘志;竿本英貴
• 通讯作者: 竿本英貴