Temperature dependent viscous behavior on natural clay and the extension of a elasto-thermo-viscoplastic constitutive model

天然粘土的温度依赖性粘性行为以及弹热粘塑性本构模型的扩展

• 批准号: 09650546
• 负责人: YASHIMA Atsushi
• 金额: $ 2.05万
• 依托单位: Gifu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650546/
• 关键词: natural clay; laboratory test; temperature dependent behavior; constitutive model; micro-structure; SEM; finite element method; 温度; 熱弾粘塑性; 力学特性; コンシステンシー; 土の構造; 室内試験; 温度依存性; 要素試験

The behavior of natural clays during one dimensional consolidation is strongly influenced by. strain rate as well as temperature. The preconsolidation pressure is a function of both strain rate and temperature. The viscous behavior of the natural clay skeleton as well as the characteristics of the permeability are discussed, based on the experimental results obtained on natural clay. Also, an elasto-thermo-viscoplastic constitutive model is developed to reproduce the one dimensional behavior of natural clays at different strain rates and temperatures. An effective stress based finite element method is applied to the experimental results of consolidation.1) For all the tests performed, the relationship between the vertical effective stress normalized with respect to the preconsolidation pressure corresponding to the strain rate and temperature at that time, and the vertical strain is unique.2) An elasto-thermo-viscoplastic constitutive model has been developed by extending the Adachi an … More d Oka's model to reproduce the behavior of natural clays at different strain rates and temperatures. The viseoplastic parameter introduced is found to depend at least as a first approximation on the temperature only through the temperature dependence of the preconsolidation pressure.3) It is found that the proposed elasto-thermo-viscoplastic constitutive model satisfactorily reproduce the one dimensional viscous behavior of the natural Berthierville clay at different strain rates and temperatures.An importance of yielding characteristic and an effect of the microstructure on stress-strain characteristics of Osaka Upper-Most Pleistocene marine clay are also studied. To get high quality clay samples, Pleistocene marine clays were sampled by block-sampling technique. Clay samples undertaken by the block-sampling technique are found to have higher quality than Pleistocene clay samples obtained by the tube : >sampling technique. The following conclusions are obtained from the present study : 1. Yielding properties of Osaka Pleistocene marine clays from the two sites are anisotropic. 2. The Pleistocene marine clay has a linkage structure with significant bonding, which induces more brittle behavior, higher compressive strength and higher stiffness than the disturbed and reconstituted samples. Less

天然粘土在一维固结过程中的行为受到强烈影响。应变率以及温度。预固结压力是应变率和温度的函数。根据天然粘土的实验结果，讨论了天然粘土骨架的粘性行为以及渗透性特征。此外，还开发了弹热粘塑性本构模型来重现天然粘土在不同应变率和温度下的一维行为。基于有效应力的有限元方法应用于固结实验结果。1) 对于所有进行的试验，相对于当时的应变率和温度对应的预固结压力归一化的垂直有效应力与垂直应变之间的关系是唯一的。2) 通过扩展 Adachi an … 更多 d Oka 模型，建立了弹热粘塑性本构模型，以再现自然的行为。 不同应变率和温度下的粘土。发现引入的粘塑性参数仅通过预固结压力的温度依赖性至少作为第一近似值依赖于温度。3）发现所提出的弹-热-粘塑性本构模型令人满意地再现了天然 Berthierville 粘土在不同应变率和温度下的一维粘性行为。屈服特性的重要性以及微观结构对 还研究了大阪最上部更新世海相粘土的应力-应变特征。为了获得高质量的粘土样品，采用块取样技术对更新世海相粘土进行了取样。发现通过块取样技术获得的粘土样品比通过管取样技术获得的更新世粘土样品具有更高的质量：>取样技术。本研究得出以下结论： 1. 两个地点的大阪更新世海相粘土的屈服特性是各向异性的。 2. 更新世海相粘土具有显着粘结的连接结构，与扰动和重构样品相比，其具有更多的脆性行为、更高的抗压强度和更高的刚度。较少的

项目成果

Yashima A., Leroueil, S., Oka, F.and Guntoro, I.: "Modeling temperature and strain rate dependent behavior of clays : One dimensional consolidation" Soils and Foundations. Vol.38, No.2. 63-73 (1998)

Yashima A.、Leroueil, S.、Oka, F. 和 Guntoro, I.：“模拟粘土的温度和应变率相关行为：一维固结”土壤和地基。

八嶋 厚: "上部大阪洪積粘土の力学特性と構造変化" 土木学会論文集. 印刷中. (1999)

Atsushi Yashima：“上大阪洪积粘土的机械特性和结构变化”，日本土木工程师学会论文集（1999 年）。

重松 宏明: "高温度環境下における粘土の力学特性に関する研究" 土木学会第53回年次学術講演会講演集. III. 72-73 (1998)

重松宏明：“高温环境下粘土力学性能的研究”第53届日本土木工程学会学术年会论文集III 72-73。

Fusao Oka: "An elasto-viscoplastic model for natural clay and its application" Proc. 6th Int. Syinpo. on Num. Models in Geomech.1. 105-110 (1997)

Fusao Oka：“天然粘土的弹粘塑性模型及其应用”Proc。

Atsushi Yashima: "Modelling Temperature and Strain Rate Dependent Behavior of Clays : One Dimensional Conselidation" Soils and Foundations. 38・2. 63-73 (1998)

Atsushi Yashima：“粘土的温度和应变率相关行为建模：一维整合”土壤和基础 63-73（1998）。