Generalization of Elastoplastic Model Using p and q for Geomaterials Based on the SMP Criterion

基于 SMP 准则的土工材料弹塑性模型的推广

• 批准号: 12650493
• 负责人: MATSUOKA Hajime
• 金额: $ 0.83万
• 依托单位: Nagoya Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650493/
• 关键词: Elastoplasticity; Constitutive equation; Three-dimension; Geomaterial; Strength; Deformation; Numerical analysis; Unsaturated soil; 弾塑性構成モデル; 3次元; 破壊規準; 降伏規準; 変換応力; 一般応力; ダイレイダンシー

1. An elastoplastic model for geomaterials in three-dimensional stresses. For applying a three-dimensional criterion the Extended SMP criterion to elastoplastic models for cohesive-frictional materials, a transformed stress based on the criterion is proposed, which is determined by making the criterion become a cone having the axis as the space diagonal in the transformed principal stress space. Furthermore, an elastoplastic model for geomaterials is presented, which takes the following three characteristics of goematerials into consideration. The first is the strength and deformation characteristics of geomaterials in three-dimensional stress; the second is the dilatancy characteristics of geomaterials; the third is the confining-pressure dependency of strength and deformation. The proposed model is capable of predicting the stress versus strain relations of geomaterials including cohesive-factional materials and granular materials in three-dimensional stress and a wide range of the c … More onfining pressure.2. Application of the proposed model to numerical analysis of rock-fill dam. In order to apply the model to practical engineering by using FEM, the elastoplastic constitutive tensor is derived. An example of the existing rock-fill dam was selected to demonstrate the usefiilness of the model in the finite element analysis for predicting deformation of geomaterials under embankment loading. The settlement and the lateral displacement of foundation computed by the proposed model fairly agree with the observed results.3. A three-dimensional elasto-plastic model for unsaturated soil. Using a transformed stress tensor based on the Extended SMP criterion, an elasto-plastic model was proposed for unsaturated soil. The influences of suction on the mechanical behavior ofunsaturated soil are taken into account in the model by using a parameter named as suction stress, which is added to net stress to form an effective stress, and associating a yield stress and model parameters with it. The proposed model needs few material parameters, which can be easily determined from the results of the ordinary tests, for example, oedometer and direct shear tests or biaxial test. It can predict the stress-strain-strength behavior of unsaturated soil under the conditions of three-dimensional stresses and constant or variable suction. A considerable number of triaxial compression and extension tests on unsaturated compacted clay were performed by using a suction controllable triaxial apparatus, to measure the stress-strain behavior under different stress paths with constant and decreasing suction. The prediction by the proposed model shows good agreement with the measured behavior of unsaturated soil not only in triaxial compression but also in triaxial extension under the conditions of constant suction and reduction in suction, which may induce an irrecoverable volumetric compression (collapse). Less

1. 三维应力下岩土材料的弹塑性模型 为了将三维准则扩展 SMP 准则应用于粘性摩擦材料的弹塑性模型，提出了基于该准则的变换应力，该应力是通过制定准则来确定的。成为以变换后的主应力空间中的轴为空间对角线的圆锥体。此外，提出了一种土工材料的弹塑性模型，该模型采用了土工材料的以下三个特征。第一是岩土材料在三维应力下的强度和变形特性；第二是岩土材料的剪胀特性；第三是强度和变形的围压依赖性。三维应力和大范围内压压力下岩土材料（包括粘性分性材料和颗粒材料）与应变关系的关系。 2．将所提出的模型应用于堆石数值分析。为了利用有限元法将模型应用到实际工程中，以现有堆石坝为例，推导了弹塑性本构张量，证明了该模型在预测岩土材料变形的有限元分析中的实用性。路堤荷载作用下的沉降和地基横向位移与观测结果相当吻合。3．基于扩展SMP准则的变换应力张量，提出了非饱和土的弹塑性模型，模型中考虑了吸力对非饱和土力学行为的影响，参数为吸力应力：添加到净应力以形成有效应力，并将屈服应力和模型参数与其相关联。所提出的模型需要很少的材料参数，这些参数可以很容易地从普通试验的结果确定，例如里程计和直剪试验。或者双轴试验可以预测三维应力和恒定或可变吸力条件下非饱和土的应力-应变-强度行为，通过吸力可控对非饱和压实粘土进行了相当多的三轴压缩和拉伸试验。三轴装置，测量具有恒定吸力和递减吸力的不同应力路径下的应力-应变行为，所提出的模型的预测结果与非饱和土的测量行为非常吻合，不仅在三轴压缩，而且在三轴拉伸条件下。持续吸力和吸力减少，可能会导致不可恢复的体积压缩（塌陷）。

项目成果

原忠, 竹澤請一郎, 工藤アキヒコ, 松岡元, 孫徳安: "築堤時のロックフィルダム材料の弾塑性モデルとFEM解析(その1)-三軸試験データによるモデルの適用性の検討-"土木学会第56回年次学術講演概要集. III-B. 598-599 (2001)

Tadashi Hara、Keiichiro Takezawa、Akihiko Kudo、Hajime Matsuoka、Tokuyasu Son：“路堤期间堆石坝材料的弹塑性模型和 FEM 分析（第 1 部分）- 使用三轴试验数据检验模型适用性 -”日本土木工程师学会第 56 届学术年会讲座摘要。598-599（2001）

孫 徳安, 松岡 元など4名: "ロックフイルダムの堤体材料の弾塑性モデルとその検証"土木学会第55回年次学術講演会. 3-B. 692-693 (2000)

Deyasu Son、Hajime Matsuoka等4人：“堆石坝路堤材料的弹塑性模型及其验证”，日本土木工程学会第55届学术年会3-B 692-693。

孫徳安, 松岡元他5名: "三軸試験によるD級軟岩の変形・強度特性"第37回地盤工学研究発表会. (発表予定). (2002)

Dean Son、Hajime Matsuoka 等 5 人：“三轴试验 D 级软岩的变形和强度特性”第 37 届岩土工程研究会议（预定报告）（2002 年）。

Sun D.A, Matsuoka H.など4名: "An anisotropic hardening elastoplastic model for clay and sand and its application to numerical analysis"Proc. of 10th Int. Conference on Computer Methods and Advances in Geomechanics. 1. 407-412 (2001)

Sun D.A、Matsuoka H. 等 4 人：“粘土和砂子的各向异性硬化弹塑性模型及其在数值分析中的应用”，第 10 届地质力学计算机方法与进展会议论文。

Sun D.A., Matsuoka H. et al.: "Deformation and strength characteristics of D-class soft rock by triaxial tests"Proceedings of the 37th Japan National Conference on Geotechnical Engineering. in press. (2002)

孙D.A.、松冈H.等：《D级软岩变形与强度特性的三轴试验》第37届日本全国岩土工程会议论文集。