Comparisons of the prediction methods for ground failure and construction of the DATA-BASE of those methods.

接地故障预测方法的比较及这些方法的数据库构建。

• 批准号: 60550350
• 负责人: SHIBATA Toru
• 金额: $ 0.96万
• 依托单位: Kyoto 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: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60550350/
• 关键词: Bearing Capacity; Circular Arc Method; Ground Improvement Method; Reinforced Earth; Visco-Plastic Algorithm; Regid-Plastic FEM; 要素境界すべりモデル

In this study, a series of stability analyses and deformation analyses were carried out by using several kinds of failure prediction methods. The main conclusions drawn from these analyses are summarized as follows.1. A series of coupled stress-flow analyses for the bearing capacity and plastic flow of a rate-sensitive, saturated clay have been made using the method of finite elements. The undrained bearing capacity of the clay foundation increases with increasing loading rate, in accordance with the associated increase in the shear strength of the clay element. Indeed, the bearing capacity factor, <N_c> , remains at a practically constant value irrespective of the loading rate. The remarkable redistribution of stress occurs within the foundation clay undergoing creep under constant loads. This phenomenon prolongs the moment of possible failure of the foundation clay much more, as compared with the fictitious case where the shear stress in the soil mass would have been maintained constant during the creep process.2. By introducing new material functions and internal variables into the viscoplastic flow rule, we could establish a viscoplastic constitutive model for normally consolidated clays. This model can describe time-dependent behavior such as the strain-rate effect on the stress-strain behavior and creep rupture including acceleration creep.3. The monitored performance of a composite breakwater has been discussed, in the light of the during-event predictions using the method of finite elements. The stability ensured during the construction stage is most clearly reflected in the low value of the ratio between maximum lateral displacement and caisson settlement. The undersea measurements of settlements have provided a set of useful information, whereby two-dimensional nature of the ground deformation can clearly be identified through the settlement profile.

在这项研究中，通过使用多种失败预测方法进行了一系列稳定性分析和变形分析。这些分析得出的主要结论总结如下1。使用有限元的方法进行了一系列的耦合应力流分析，以进行对速率敏感的饱和粘土的轴承能力和塑性流。根据粘土元件的剪切强度的相关增加，粘土粉底的不排水轴承能力随着载荷速率的增加而增加。实际上，轴承能力因子<n_c>在实际上保持恒定的价值，而与负载率无关。压力的显着重新分布发生在基础粘土中，在恒定载荷下经历了蠕变。与虚拟的情况相比，这种现象延长了基础粘土可能失败的时刻，在蠕变过程中，土壤质量中的剪切应力将保持恒定。2。通过将新的材料功能和内部变量引入粘膜流量规则，我们可以为正常合并的粘土建立粘性构成模型。该模型可以描述时间依赖性行为，例如应变率对应力 - 应变行为的影响和包括加速度蠕变（加速度蠕变）的蠕变。3。鉴于使用有限元的方法进行事件预测，已经讨论了复合防波堤的受监测性能。确保在施工阶段确保的稳定性最清楚地反映在最大横向位移和Caisson沉降之间的低值。定居点的海底测量结果提供了一组有用的信息，从而可以通过结算概况清楚地识别地面变形的二维性质。

项目成果

八嶋厚: 土質工学会関西支部講習会テキスト. 1. 80-135 (1986)

Atsushi Yashima：日本土壤工程学会关西分会研讨会文本。1. 80-135 (1986)。

田村武: 土質工学会関西支部講習会テキスト. 1. 50-79 (1986)

Takeshi Tamura：日本土壤工程学会关西分会研讨会文本。1. 50-79 (1986)。

Toshihisa ADACHI: "An Elasto-Viscoplastic Theory for Clay Failure." Proc. 8th Asia Regional Conference on SMFE. (1987)

Toshihisa ADACHI：“粘土破坏的弹粘塑性理论。”

Mimura Mamoru: Bull,Disas.Prev.Res.Inst,Kyoto Univ.36. (1986)

Mimura Mamoru：Bull，Disas.Prev.Res.Inst，京都大学 36。

Takeshi TAMURA: "Fundamentals and Applicabilities of Rigid-Plastic FEM." Textbook in a short course, The Japanese Society of SMFE, Kansai Branch. 1. 50-79 (1986)

Takeshi TAMURA：“刚塑性有限元的基础知识和应用。”