Predict Failure of Shirasu Slope in Consideration of Patterns of Rainfall and Unsaturated Seepage

考虑降雨和非饱和渗流模式的 Shirasu 边坡破坏预测

• 批准号: 02650350
• 负责人: OKABAYASHI Takumi
• 金额: $ 1.22万
• 依托单位: Kagoshima National College of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02650350/
• 关键词: Rainfall; Special Soil; Shirasu; Slope Stability; Seepage; Volumetric Water Content; Pressure Head; Finite Element Method; 火山噴出物; 火山灰; 斜面安定; 不飽和浸透; 降雨パタ-ン; 土質力学

Shiras is a pumic-flow deposit soil widely distributed in southern Kyushu and oilier districts in Japan, and is counted to be a typical collapsible soil for its frequent damages mainly owning to rainfall and earthquakes. Such a soil seems to be similar to the yellow-brown pumice soil in North Island, New Zealand, the cemented-sand in the U. S. A., and the volcanic ash soil in Central America. The strength characteristics of the undisturbed Shirasu are different from those of the disturbed Shirasu, since undisturbed samples have tensile strengh due to a geological cause.It is well known that Shirasu becomes very collapsible after increasing the moisture content. Many studies on failure of slope by rainfall have been done by many laboratories. The failure mechanism of Shirasu has not been clarified yet, because the mechanisum of it by rainfall is very complicated.The conclusion drawn were as follows ;(1) The patern of rainfall in Southern Kyushu was become clear.(2) This study make it clear about the relation between unsaturated coefficent of permeability, water content by volume and suction of Shirasu.(3) The triaxial test results make clear characteristics of soil mechanics and liquefaction in Shirasu.(4) This paper refers to characteristics of unsaturated seepage of Shirasu slopes in raifall.

白层土是广泛分布于日本九州岛南部及其他地区的一种浮岩流存款土，因其在降雨和地震等灾害中频繁发生而被认为是一种典型的湿陷性土。这种土壤似乎与新西兰北岛的黄褐色浮石土、美国的水泥砂土、英国的水泥砂土、英国的水泥砂土和英国的水泥砂土相似。S.一、和中美洲的火山灰土壤。由于地质原因，未扰动的白砂具有抗拉强度，因此其强度特征与扰动的白砂不同。众所周知，白砂在含水量增加后会变得非常湿陷。许多实验室对降雨引起的边坡破坏进行了大量的研究。由于降雨对白须的破坏机理十分复杂，至今尚未弄清其破坏机理，本文得出以下结论：（1）九州南部的降雨模式变得清晰。(2)研究结果明确了非饱和渗透系数、体积含水率与白须吸力的关系。(3)三轴试验结果表明，白洲地区的土力学特性和液化特性较为明显。(4)本文研究了降雨条件下白须边坡的非饱和渗流特性。

项目成果

村田 秀一,兵動 正幸,安福 規之,岸本 洋,岡林 巧,山本 陽一: "乱したしらすの非排水繰返しせん断特性" 第27回土質工学研究発表会講演集. (1992)

Shuichi Murata、Masayuki Hyodo、Noriyuki Yasufuku、Hiroshi Kishimoto、Takumi Okabayashi、Yoichi Yamamoto：“受干扰银鱼的不排水循环剪切特性”第 27 届土壤工程研究会议论文集（1992 年）。

岡林 巧,杉尾 哲,木原 正人,村尾 俊行: "乱さないしらすの不飽和浸透特性" 土木学会西部支部研究発表会講演概要集. 468-469 (1991)

Takumi Okabayashi、Tetsu Sugio、Masato Kihara、Toshiyuki Murao：“不受干扰的银鱼的不饱和渗透特性”日本土木工程师学会西部分会摘要 468-469 (1991)。

H. MURATA: "Undrained Cyclic Shear Characteristics of Shirasu" The 27th Japan Ntional Conference on Soil Mechanics and Foundation Engineering. (1992)

H. MURATA：“Shirasu 的不排水循环剪切特性”第 27 届日本全国土壤力学和基础工程会议。

桑畑 英紀,杉尾 哲,岡林 巧: "しらす地盤における野外浸透実験" 土木学会西部支部研究発表会講演概要集. 304-305 (1992)

Hideki Kuwabata、Tetsu Sugio、Takumi Okabayashi：“银鱼地面的现场渗透实验”日本土木工程师学会西部分会的演讲摘要 304-305 (1992)。

岡林 巧,村田 秀一,兵動 正幸,安福 規之,山本 陽一,岸本 洋: "乱したしらすの非排水せん断特性" 第27回土質工学研究発表会講演集. (1992)

Takumi Okabayashi、Shuichi Murata、Masayuki Hyodo、Noriyuki Yasufuku、Yoichi Yamamoto、Hiroshi Kishimoto：“受干扰银鱼的不排水剪切特性”第 27 届土壤工程研究会议论文集（1992 年）。