Study on evaluation of stability of slope holding discontinuous plane causing slope failure

导致边坡失稳的边坡稳定性评价研究

• 批准号: 15560427
• 负责人: YAMAMOTO Tetsuro
• 金额: $ 1.34万
• 依托单位: Yamaguchi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15560427/
• 关键词: discontinuous plane; slope failure; safety factor; rainfall; in-situ shear test; field survey; tree root; direct box shear test; 斜面崩壊; 安定性; 模型実験; 表層崩壊; 一面せん断; 断層

According to our field survey, slope failure frequently occurred along a discontinuous plane during tiny rainfall. The discontinuous planes resulting in slope failures were classified as following : 1) fractured clay in landslide area, 2) schist developed in slate, 3) thin glossy black soil adhered to joint or schist in metamorphic rock, 4) boundary plane between weakly and strongly weathered granite rocks, and 5) clay-seam interpenetrated in granite rock. During two years from 2003 to 2004, we investigated 37 sites of slope disasters occurred in Yamaguchi prefecture and then measured shear strength mobilized on the discontinuous plane in the site or the laboratory using an ultra simplified in-situ shear test apparatus. Also the direct box shear tests were performed on two types of Masado that were sampled in Ube and Iwakuni, to demonstrate the validity of the in-situ test. These test results suggested that the strength parameter obtained by the in-situ test should be used in the stability analysis of cut slopes having the discontinuous planes. Secondly, weathered slopes of the Kanmon group were surveyed on six risk factors such as height of slope, rainfall, folding etc. A fault was regarded as one of the discontinuous planes. Slopes that have the fault on the top and two more factors are prone to collapsing. The results should be effective to determine the inclinations of cut slopes. Thirdly, the tree root was taken up as an important factor related to surface failure. The direct box shear test was performed on Ube Masado mixed with tree roots. The test results showed that an increase of the apparent cohesion remarkably exhibited rather than that of the internal friction angle under condition of low overburden pressure. Finally, if the discontinuous planes are seen inside a slope, it means that possibility causing slope failure is high.

根据我们的现场调查，在微小的降雨期间，经常沿着不连续的平面发生斜坡故障。导致斜坡故障的不连续平面分类为以下：1）在滑坡区域中骨折的粘土，2）在板岩中开发的片岩，3）3）稀薄的光泽黑色土壤粘附在变质岩石中的关节或片岩中，4）在虚弱和强烈风化的花岗岩岩石之间的边界平面，以及5）粘土的粘土岩石岩石岩石岩石岩石中，在Granite Internite intrinite intrinite intrinite intrinite intrinite intrinite intranite intranite intranite intranite intranite intranite intarite intranite intarite intarite intarite intarite intranite。从2003年到2004年的两年中，我们研究了37个斜坡灾难的地点，在山口县发生，然后使用超简化的位于原地的剪切剪切测试设备测量了位点或实验室中不连续平面上动员的剪切强度。另外，对在UBE和Iwakuni采样的两种类型的Masado进行了直接盒剪切测试，以证明原位测试的有效性。这些测试结果表明，通过原位测试获得的强度参数应用于具有不连续平面的切割斜率的稳定性分析。其次，对Kanmon组的风化斜率进行了调查，以六个危险因素，例如斜坡，降雨，折叠等。故障被视为不连续的平面之一。顶部有故障的斜率和另外两个因素很容易崩溃。结果应有效地确定切开斜率的倾斜。第三，将树根作为与表面故障有关的重要因素。直接盒剪切测试是在Ube Masado上与树根混合的。测试结果表明，在低承载压力的条件下，表观内聚力的增加表现出明显的表现，而不是内部摩擦角的增加。最后，如果在斜坡内看到不连续的平面，则意味着导致斜率故障的可能性很高。

项目成果

表層土の一面せん断試験における根茎の影響

根茎对表土单面剪切试验的影响

• 发表时间: 2004
• 期刊: 自然災害研究協議会西部地区部会報・研究論文集 28号
• 作者: 川内崇文;江藤崇;廣岡明彦;西岡佑介;鈴木 素之
• 通讯作者: 鈴木 素之

Slope disasters caused by heavy rainfalls in Yamaguchi prefecture, 2004

2004年山口县强降雨引发的斜坡灾害

• 发表时间: 2005
• 期刊: Western Regional Division Report of Natural Disaster Research Council No.29
• 作者: Tetsuro Yamamoto;Motoyuki Suzuki;Naoki Takeda;Tomohiro Tomokiyo;Emi Kamimura;Yoichi Sehara;Takashi Terayama
• 通讯作者: Takashi Terayama

Effect of roots on strength of surface soil in direct shear test

直剪试验中根系对表土强度的影响

• 发表时间: 2004
• 期刊: Western Regional Division Report of Natural Disaster Research Council No.28
• 作者: Motoyuki Suzuki;Yousuke Biwa;Tetsuro Yamamoto
• 通讯作者: Tetsuro Yamamoto

河内 義文: "山口県豊田町の切土による斜面崩壊について"自然災害研究協議会西部地区部会報・研究論文集. 28号. 43-46 (2004)

河内义文：“山口县丰田町因切割导致的斜坡失陷”自然灾害研究会西区部公报/研究论文第 28. 43-46 号（2004 年）。

Failure of a cut-slope consisting of the Kanmon group

由 Kanmon 群组成的边坡破坏

• 发表时间: 2004
• 期刊: TSUCHI-TO-KISO, JGS Vol.52,No.11
• 作者: Tetsuro Yamamoto;Motoyuki Suzuki;Naoki Takeda;Akie Enomoto;Tomoko Ikeda;Yoshifumi Kochi
• 通讯作者: Yoshifumi Kochi