Constitutive Modelling and Determination of Soil Parameters for Anisotropically Consolidated Clay

各向异性固结粘土的本构模型和土壤参数的确定

• 批准号: 62550353
• 负责人: MITACHI Toshiyuki
• 金额: $ 1.28万
• 依托单位: Hokkaido 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: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62550353/
• 关键词: Anisotropy; Constitutive Equation of Soil; Pore Water Pressure; Stress History; Stress Relaxation; Stress-strain Curve; Triaxial Compression Test; 非排水クリープ; 間隙圧; 三軸圧縮試験; 時間的効果; 粘土

1. On the stress-strains-time behavior of normally consolidated clay ;A series of undrained triaxial stress relaxation tests on four saturated clays consolidated under isotropic stress condition and constant rate of strain triaxial compression test on a saturated clay consolidated under isotropic and anisotropic stress conditions were performed. Experimental results show that the principal stress difference versus logarithm of time relationship during stress relaxation test is approximated by the two straight lines independent of strain level, strain rate and mode of stress application in the preceding undrained shear process. Stress ratio versus strain relationship is not affected by the rate of strain during shear, and the porepressure during shear decreases with the increase in the rate of strain.2. On the stress-strain-time equation for anisotropically normally consolidated clay ;Based on the test results mentioned above, a new elasto-viscoplastic constitutive equation for anisotro … More pically consolidated clay was proposed. It was found that the proposed equation can predict fairly well the effect of rate of strain on the undrained stress-strain behavior, stress relaxation and also undrained creep behavior of anisotropically consolidated clay.3. On the elasto-plastic constitutive model for anisotropically overconsolidated clay ;A series of drained stress probe tests along six stress paths for the specimens consolidated and rebounded under anisotropic stress condition were conducted to investigate the influence of anisotropic stress history and stress path on the stress-strain behavior of overconsolidated clay.From the test results, it was found that the shear strain during shear depends not only on the change of stress ratio but also on that of mean effective stress, and that K_ overconsolidated clay exhibits negative dilatancy at the beginning of loading even on the "dry side", and then significant positive dilatancy is observed on the stress path moving towards the Hvorslev surface on the dry side. Based on the test results, a constitutive model for anisotropically overconsolidated clay was proposed. Stress-strain behavior for the stress path moving towards the critical state line and also for the stress paths directed from the overconsolidation state to the normal consolidation zone can be well predicted by the model. Less

1.正常固结粘土的应力-应变-时间特性进行了4种各向同性应力条件下固结的饱和粘土的不排水三轴应力松弛试验和1种各向同性和各向异性应力条件下固结的饱和粘土的常应变率三轴压缩试验。试验结果表明，在不排水剪切过程中，主应力差与时间对数的关系可用两条直线近似，与应变水平、应变速率和应力施加方式无关。剪切过程中的应力比-应变关系不受应变率的影响，剪切过程中的孔隙水压力随着应变率的增大而减小.关于各向异性正常固结粘土的应力-应变-时间方程在上述试验结果的基础上，提出了一个新的各向异性正常固结粘土的弹粘塑性本构方程 ...更多信息 提出了固结粘土的概念。结果表明，该方程能较好地预测应变率对各向异性固结粘土的不排水应力-应变特性、应力松弛以及不排水蠕变特性的影响.各向异性超固结粘土的弹塑性本构模型为研究各向异性应力历史和应力路径对超固结粘土应力-应变特性的影响，对各向异性应力条件下固结回弹的超固结粘土试件进行了沿着6条应力路径的排水应力探针试验。结果表明，剪切过程中的剪应变不仅与应力比的变化有关，而且与平均有效应力的变化有关，K_2超固结粘土在加载初期甚至在“干侧”也表现出负的剪切力，然后在向干侧上的Hvorslev表面移动的应力路径上观察到显著的正双折射。根据试验结果，提出了各向异性超固结粘土的本构模型。该模型可以很好地预测应力路径向临界州线方向移动以及从超固结状态向正常固结区方向移动的应力-应变行为。少

项目成果

池浦勲: 土質工学会北海道支部技術報告集. 29. 113-118 (1989)

Isao Ikeura：日本土壤工程学会北海道分会技术报告集。29. 113-118 (1989)。

池浦勲: 土質工学会北海道支部技術報告集. 28. 69-74 (1988)

Isao Ikeura：日本土壤工程学会北海道分会技术报告集 28. 69-74 (1988)。

Junichi Mizukami: "Stress-strain behavior of saturated clay under anisotropic stress condition" Proc., 42th Annual Meeting of JSCE. III. 178-179 (1987)

Junichi Mizukami：“各向异性应力条件下饱和粘土的应力应变行为”Proc.，第 42 届 JSCE 年会。

池浦勲: 土木学会年次学術講演会概要集. 42. 202-203 (1987)

Isao Ikeura：日本土木工程师学会年会学术会议摘要集。 42. 202-203 (1987)。

木幡行宏: 土質工学会北海道支部技術報告集. 28. 87-94 (1988)

Yukihiro Kobata：日本土壤工程学会北海道分会的技术报告。28. 87-94 (1988)。