Quantification of non-coaxiality in constitutive relationship of clays and its application to limit equilibrium problem

粘土本构关系中非同轴性的量化及其在极限平衡问题中的应用

• 批准号: 08650571
• 负责人: IIZUKA Atsushi
• 金额: $ 1.28万
• 依托单位: Kobe University (1997)Kanazawa University (1996)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650571/
• 关键词: shear deformation; shear band; strain localization; non-coaxiality; soil; water coupled problem; strength; F.E.simulation; 進行性破壊

Recently, localized deformation in geo-materials has attracted many researchers with expecting rational explanation of phenomena such as progressive failure and size effect of footing on bearing capacity. The mathematical formulation of initial-boundary value problem for saturated soil mass is presented and the finite element technique is applied to solve it under appropriate initial and boundary conditions. The elastoplastic Cam-clay model is employed for the soil skeleton. In this study the theoretical framework for the soil/water coupled problem is extended to the finite deformation field where bifurcation of solutions in an initial boundary value problem may occur. The discretization for governing equations is proposed. After examining the numerical stability of the finite element scheme, the triaxial compression shear test of a clay specimen is simulated under the plane strain condition. It is revealed that the shear band observed as the strain localization in clay specimen always develops with dilation, which can be called the localization of dilatancy. Moreover is examined the applicability of such non-linear soil/water coupled formulation in the engineering practice in this study.

近年来，岩土材料的局部变形引起了许多研究人员的关注，他们期待对渐进破坏和基础对承载力的尺寸效应等现象做出合理的解释。提出了饱和土体初始边值问题的数学公式，并在适当的初始和边界条件下应用有限元技术对其进行求解。土骨架采用弹塑性 Cam-clay 模型。在这项研究中，土/水耦合问题的理论框架被扩展到有限变形场，其中初始边值问题的解可能发生分歧。提出了控制方程的离散化。在检验有限元方案的数值稳定性后，在平面应变条件下模拟了粘土试件的三轴压剪试验。结果表明，在粘土样品中作为应变局部化观察到的剪切带总是随着膨胀而发展，这可以称为剪胀性局部化。此外，本研究还检验了这种非线性土/水耦合公式在工程实践中的适用性。

项目成果

Ohta, H., et al.: "Interpretation of in-situ and laboratory tests on soft clays" Proc. of Int. Conf. on Site Characterization. (1998)

Ohta, H. 等人：“软粘土现场和实验室测试的解释”Proc。

飯塚敦他: "構造工学における計算力学の基礎と応用(第6章2節,第9章6節)" 土木学会, 577 (1996)

Atsushi Iizuka 等人：“结构工程中计算力学的基础和应用（第 6 章第 2 节、第 9 章第 6 节）”日本土木工程师学会，577（1996）

森川 嘉之, 他: "粘性土の等体積一面せん断強さ" 土木学会論文集. 582 1III-41. 173-182 (1997)

Yoshiyuki Morikawa 等人：“粘性土的等体积剪切强度”，日本土木工程师学会会刊 582 1III-41 (1997)。

Iizuka, A., Kobayashi, I.and Ohta, H.: "Dilatancy localization in clay specimen under shearing" Proc.of 4^<th> International Workshop on Localization and Bifurcation Theory for Soils and Rocks. (under submitting). (1998)

Iizuka, A.、Kobayashi, I. 和 Ohta, H.：“剪切下粘土样本的剪力局部化”Proc.of 4^<th> 国际土壤和岩石局部化和分岔理论研讨会。

小林 一三, 他: "土/水連成有限要素解析に基づいた限界盛土高さ推定法" 土木学会論文集. 575 1III-40. 207-217 (1997)

Ichizo Kobayashi 等人：“基于耦合土/水有限元分析的有限路堤高度估算方法”，日本土木工程师学会汇刊 575 1III-40 (1997)。