Cyclic and anisotropic elasto-viscoplastic behavior of clay and constitutive model

粘土的循环和各向异性弹粘塑性行为及本构模型

• 批准号: 04650434
• 负责人: OKA Fusao
• 金额: $ 1.28万
• 依托单位: Gifu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650434/
• 关键词: Clay; Elastoviscoplasticity; Constitutive model; Cyclic test; Non-linear kinematical hardening rule; Multiaxial test; Torsional test; Triaxial test; 三軸試験

Natural soft clay was sampled at both Osaka and Akita by use of modified large diameter Laval sampler in which the angle of cutting edge was improved. Triaxial tests, torsional tests were performed under the undrained conditions, in addition, multiaxial tests were carried out under undrained plane strain conditions after isotropic consolidation. In the plane strain tests, it is observed that the stress path is quite different from the results for remolded clay samples. Immediate principle stress greatly varies during the deformation. In an early part of straining, b value changes in small amount and reaches about 0.5 at large strain. As for the cyclic elasto-viscoplastic constitutive model, the proposed model based on the non-linear hardening rule was discussed for the results of cyclic isotropic consolidation test. We have found that the proposed model is applicable to both cyclic shearing and cyclic isotropic compression. In the modeling, both linear and non-linear hardening are considered in order to prevent an over-ratcheting effect. In addition, an isotropic hardening rule are used with kinematical hardening rule to describe a deterioration of shear modulus.

利用改装的大直径拉瓦尔取样器对大阪和秋田两地的天然软粘土进行了取样，改进了取样器的刃口夹角。在不排水条件下进行了三轴试验、扭转试验，在各向同性固结后进行了不排水平面应变条件下的多轴试验。在平面应变试验中，观察到重塑粘土的应力路径与重塑粘土的结果有很大的不同。直接主应力在变形过程中变化很大。在应变初期，b值变化不大，大应变时b值可达0.5左右。对于循环弹粘塑性本构模型，根据循环各向同性固结试验结果，讨论了基于非线性硬化准则的模型。我们发现，该模型既适用于循环剪切，也适用于循环各向同性压缩。在建模中，同时考虑了线性硬化和非线性硬化，以防止过度棘轮效应。此外，用各向同性硬化法则和运动硬化法则来描述剪切模数的劣化。

项目成果

Fusao Oka: "Acyclic elasto-viscoplastic constitutive model for clay based on the non-linear hardening rule" Proc.4th Int.Symp.on Numerical Models in Geomechanics,(Balkema). 105-114 (1992)

Fusao Oka：“基于非线性硬化规则的粘土非循环弹粘塑性本构模型”Proc.4th Int.Symp.on Numerical Models in Geomechanics，（Balkema）。

Fusao Oka: "Anisotropic and pseudo-anisotropic elasto-visciplastic constitutive model for clay" Modern Approches to Plasticity. 505-526 (1993)

Fusao Oka：“粘土的各向异性和伪各向异性弹粘塑性本构模型”现代塑性方法。

Fusao Oka: "An elasto-viscoplastic constitutive model for clay using a transformed stress tensor" Mechanics of Materials. 16. 47-53 (1993)

Fusao Oka：“使用变换后的应力张量的粘土弹粘塑性本构模型”材料力学。

Fusao Oka: "A cyclic elasto-viscoplastic constitutive model for clay based on the non-linear hardening rule" Proc.4th Int.Symp.on Numerical Models in Geomechanics,(Balhema). 105-114 (1992)

Fusao Oka：“基于非线性硬化规则的粘土循环弹粘塑性本构模型”Proc.4th Int.Symp.on 地质力学数值模型，（Balhema）。

Fusao Oka: "A cyclic elasto-viscoplastic constitutive model for clay based on the non-linear hardening rule" Proc.4th Int.Symp.on Numericul Models in Geomechanics. 105-114 (1992)

Fusao Oka：“基于非线性硬化规则的粘土循环弹粘塑性本构模型”Proc.4th Int.Symp.on Numericul Models in Geomechanics。