RESEARCH ON DEFORMATION AND STRENGTH CHARACTERISTICS OF SANDS AND SOFT ROCK GROUND UNDER HIGH PRESSURE CIRCUMSTANCE.

高压环境下砂土、软岩地基变形及强度特性研究。

• 批准号: 02452195
• 负责人: TOKI Shosuke
• 金额: $ 2.5万
• 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 (B)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-02452195/
• 关键词: Bearing Capacity; Deformation; Mechanical Characteristic; Sand; Soft Rock; Strength; Physical Characteristic; Primary property; 砂質土; 変形・強度特性; 粒土分布; 粒子の破砕性; 拘束圧依存性; 褶曲作用; 降伏圧力; 粒度分布

A series of experimental and analytical examinations was carried out to investigate the effects of several influencing factors, such as stress state, primary properties of sand particles, physical and mechanical properties of sands, on the deformation-strength behavior of sands and soft rocks.For sands, 200 kind of sand samples with different primary properties were prepared.The relationships between the index properties, such as grain density, shape and size distribution were investigated, It was proven, that some index properties such as maximum and minimum void ratio, crushability characterize physical property of sands.The significant influence of the primary properties on the deformation-strength characteristics was also clarified, From the test results, the relationships of deformation-strength properties of sands with index physical properties are discussed ; the significant influence of grain shape, grading and crushability on the mechanical behaviors are presented.To investiga … More te the strength-deformation characteristics of soft rock, samples from horizontal and vertical directions were secured from the dam construction site, where strata were folded by horizontal thrust. Interesting information on the anisotropic characteristics of permeability, failure and residual triaxial strength, and yielding confining pressure were obtained. Significant effects of stress history on the mechanical behavior of soft rock, were pointed out.Deformation and failure mechanism of soft rock ground were investigated by several series of loading tests on model circular footing on artificial soft rock grounds. The effects of geometry of ground, footing size, mechanical properties of ground materials and relative position of footing from the top of slope were examined in connection with the type of failure mode ; general shear mode or large deformation with punching failure mode.Modified slice method was proposed and applied to the calculation of the ultimate bearing capacity of circular footing beside slope. While 2-dimentional calculation gave unacceptable under estimate, 3-dimentional calculation gave the reasonable estimate for the variation of ground material, slope angle, and the vicinity of the footing to the slope. Less

本文通过一系列的试验和分析研究，探讨了应力状态、砂粒的基本性质、砂粒的物理力学性质等因素对砂和软岩变形-强度特性的影响。对于砂，制备了200种不同基本性质的砂样，研究了砂的颗粒密度、砂粒的粒径、试验结果表明，最大孔隙比、最小孔隙比、可压碎性等指标表征了砂土的物理性质，并阐明了主要性质对砂土变形-强度特性的重要影响，讨论了砂土变形-强度特性与指标物理性质的关系;指出了颗粒形状、颗粒级配和破碎性能对力学性能的重要影响， ...更多信息 为研究软岩的强度变形特性，在水平推力作用下发生褶皱的坝址区，采集了水平和垂直两个方向的软岩试样。获得了渗透率、破坏和残余三轴强度以及屈服围压的各向异性特征的有趣信息。指出了应力历史对软岩力学特性的重要影响，通过对人工软岩地基上圆形基础模型的系列加载试验，研究了软岩地基的变形破坏机理。分析了地基几何形状、基础尺寸、地基材料的力学性质以及基础与坡顶的相对位置对基础破坏模式（一般剪切破坏模式和大变形冲切破坏模式）的影响，提出了修正条分法，并将其应用于边坡边圆形基础的极限承载力计算。虽然二维计算给出了不可接受的低估，三维计算给出了合理的估计的变化，地面材料，边坡角，和附近的基础的斜坡。少

项目成果

Miura K.: "Mechanical Characteristics of Sands with Different Primary Properties." Soils and Foundation. (To be published).

Miura K.：“具有不同主要特性的沙子的机械特性。”

Nishimura M.: "Failure Mechanism in Rock Ground Observed in Model Footing Test." Proc.of the Int.Symposium on Deformation and Progressive Failure in Geomechanics.(to be published).

Nishimura M.：“模型基础测试中观察到的岩石地面破坏机制。”

前田 健一: "砂粒子が構成する楕円構造体の変形解析" 土質工学研究発表会論文報告集. 28. (1993)

Kenichi Maeda：“由沙粒组成的椭圆结构的变形分析”土壤工程研究会议论文集28。（1993）。

Miura K.: "Method of Measurement for the Angle of Repose of Sand." Soils and Foundation.(to be published).

Miura K.：“沙子休止角的测量方法”。

谷瀬 敦: "人工軟岩の支持力模型実験" 土質工学研究発表会論文報告集. 28. (1993)

Atsushi Tanise：“人造软岩的支撑能力模型实验”土壤工程研究会议论文集28。（1993）。