A Study on Rupture Occurrence and Progression due to Seepage Forces

渗流力引起的破裂发生和进展的研究

• 批准号: 63550360
• 负责人: UNO Takao
• 金额: $ 1.34万
• 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: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63550360/
• 关键词: Hydraulic Fracturing; Seepage Force; Hydraulic Gradient; Laboratory Test; Heterogeneity; Finite Element Method; 浸透破壊; 限界動水勾配; 進行性破壊; 土粒子性状; シミュレ-ション; 水平一次元透水場; 全体破壊; 局部破壊; 土粒子形状; 土粒子噛み合い効果

Laboratory tests are carried out for investigating the rupture occurrence and its progression of the hydraulic fracturing within an one-dimensionally horizontal flow domain.These tests give the conclusions ; (1) The initial rupture occurs at the hydraulic gradient of 0.1-0.3 times as small as critical one in vertically flow, (2) The shape, size and density of soil particle take an effect of the occurrence of seepage failure. According to the simple two-dimensional tests, namely, two types of seepage flow, the following are recognized (3) The direction and speed of the rupture progression varies in spite of homogeneous sample, and depends on the local heterogeneity in soil mass, (4) Bearing capacity at the ground surface falls down at the early stage of rupture progression.From another two-dimensional experiment with bending flow zone, it is found out that : (5) The progression pattern is (1) heave at the down-stream ground surface -> (2)break-down at bending point-> (3) vertically progression reached to the surface. (6) Summation of the effective weights above bending elevation can be one of indices when we predict the failure occurrence over and near the bending zone.The computer simulations are also developed by the aids of (a) steady state seepage flow model, (b) unsteady seepage flow through deformable material model, (c) probabilistic model.

通过室内试验，研究了一维水平流场中水力压裂破裂的发生和发展规律。（1）垂直流中，初始破裂发生在0.1-0.3倍临界水力梯度的水力梯度处;（2）形状，土颗粒的尺寸和密度对渗透破坏的发生有影响。通过简单的二维渗流试验，即两种渗流模式，认识到：（3）无论是何种均质土样，破裂发展的方向和速度都是不同的，并取决于土体的局部非均匀性;（4）在破裂发展的早期，地面福尔斯承载力下降。结果表明：（5）其发展规律为：（1）下游地表起伏->（2）弯曲点破裂->（3）垂直向地表发展。(6)弯曲高程以上的有效权重之和可以作为预测弯曲区及其附近破坏发生的指标之一，并分别采用稳态渗流模型、变形材料非稳态渗流模型和概率模型进行了计算机模拟。

项目成果

宇野尚雄: 第23回土質工学研究発表会発表講演集. 1857-1858 (1988)

Hisao Uno：1857-1858 年第 23 届土壤工程研究会议论文集（1988 年）。

Takeshi Sato: "Probabilistic Approach to Hydraulic Fracturing in Heterogeneous Soil." Proc. of the VIII Int. Conf. on Computational Methods in WatResources, 1990.

Takeshi Sato：“非均质土壤水力压裂的概率方法。”

TAKESHI SATO: "Probabilistic Approach to Hydradic Fractwing in Heterogeneous Soil." Proc.of VIII Int.Conf.on “CMWR". (1990)

佐藤武 (TAKESHI SATO)：“异质土壤中水力分形翼的概率方法。”Proc.of VIII Int.Conf.on“CMWR”(1990)。

宇野尚雄: "浸透破壊における限界動水勾配と限界流速" 土質工学会中部支部第1回地盤工学シンポジウム発表講演集. 27-32 (1989)

Nao Uno：“渗流破坏中的临界水力梯度和临界流速”第一届岩土工程研讨会论文集，日本土壤工程学会中部分会 27-32 (1989)。

Takao Uno: "Critical Hydraulic Gradient and Critical Velocity causing Seepage Failure." Proc. of the 1st Regional Symposium on Geotechnical Engineering, pp.27-32, 1989.

Takao Uno：“导致渗漏失效的临界水力梯度和临界速度。”