Engineering Properties of Unsaturated Cohesive Soil subjected to Freezing and Thawing

冻融作用下非饱和粘性土的工程特性

• 批准号: 04650433
• 负责人: OGAWA Shoji
• 金额: $ 1.34万
• 依托单位: Nagaoka University 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: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650433/
• 关键词: Frost heaving disaster; Freezing-thawing phenomena; Unsaturated soil; Open system; Closed system; Suction force; 凍結ー融解作用; 凍上

Road pavement and gutter have been damaged due to frost heaving of the subgrade and the subbase in winter and decreasing of shearing resistance of soils of the subbase in spring.Considering those phenomena, this study aimes to make appear the actual damade conditon in field and engineering properties of soils subjected to freezing and thawing in laboratory.The results of those studies are as follows ;1.Field Resarches(1) Many frost heaving disasters occcured in Akita, Iwate and Fukushima prefectures in 1984-1986. Especially, in 1986, number of damages were 752, 1648 and 1958 in each prefectures. Also frost heaving disasters have occured every yeares at the cold region in Nagano, Yamanashi and Gunma prefectures.(2) Those frost heaving disasters were caused at the high grround water region in Hokkaido and even at the low ground water area on the cold region in Nagano, Yamanashi and Gunma prefectures if the subbase has the high water content.2.Laboratory Tests(1) In the open system tests, frost heaving occured easily in the silty soils. However, it was scarcely caused in sandy soils because those soils had high permeability.(2) In the closed system, volume changes of the unsaturated soil during freezing process resulted in expansion and shrinkage phenomenen according to the degree of the saturation of soil and during melting process shrinkage phenomena were always caused.(3) It was cleared that the shearing strength of the unsaturated soil subjected to freezing and thawing was decreased due to decreasing of the suction force between soil particles.

针对冬季路基和底基层冻胀、春季底基层土体抗剪能力下降等原因，路基路面和排水沟受到破坏，本研究旨在通过室内冻融试验，了解冻融土体在野外的实际破坏情况和工程性质。特别是1986年，每个县的损害数量分别为752起、1648起和1958起。此外，长野县、山梨县、群马县寒区每年都会发生冻胀灾害。(2)北海道高水位区冻胀灾害发生在北海道高水位区，如果底基层含水率高，长野、山梨县、群马县寒区低地下水位区也会发生冻胀灾害。2.室内试验(1)在开放系统试验中，粉质土极易发生冻胀。在封闭系统中，非饱和土体在冻结过程中的体积变化会根据土体的饱和程度而导致膨胀和收缩现象，而在融化过程中往往会产生收缩现象。(3)明确了非饱和土体在冻融过程中由于土颗粒间吸力的减小而导致抗剪强度降低。

项目成果

Tomoyoshi Nishimura: "Influence of freezing and thawing on volume of unsaturated soil" International symposium on pre-failure deformation characteristics of geomaterials IS-Hokkaido. (to be published). (1994)

西村智义：“冻融对非饱和土体积的影响”岩土材料破坏前变形特征国际研讨会IS-Hokkaido。

T.Nishimura, S.Ogawa and T.Wada: ""Influence of Freezing and Thawing on Effective Stress and Shearing Strength of Unsaturated Soils (in Japanese)" Proc.of JSCE. NO.475. 59-67 (1993)

T.Nishimura、S.Okawa 和 T.Wada：“冻融对非饱和土有效应力和抗剪强度的影响（日文）”Proc.of JSCE. NO.475. 59-67 (1993)

T.Nishimura, S.Ogawa and K.Tsukada: ""Volume Change of Unsaturated Cohesive Soils subjected to Three Dimentional Freezing" (in Japanese)" Proc.of Symposium on Frost Disaster Measure and Utilization of the Cold. 93-98 (1992)

T.Nishimura、S.Okawa 和 K.Tsukada：“三维冻结作用下不饱和粘性土的体积变化”（日语）”霜冻灾害措施和寒冷利用研讨会论文集。

塚田賢一郎: "クローズドシステムで凍結-融解作用を受けた不飽和粘性土の体積変化とせん断強さ" 土質工学研究発表会発表講演集. (発表予定). (1994)

Kenichiro Tsukada：“封闭系统中冻融作用下非饱和粘土的体积变化和剪切强度”土壤工程研究会议论文集（待发表）（1994）。

塚田 賢一郎: "クローズドシステムで凍結-融解作用を受けた不飽和粘性土の体積変化とせん断強さ" 第29回土質工学研究発表会概要集. (発表予定). (1994)

冢田健一郎：“封闭系统中冻融作用下非饱和粘土的体积变化和剪切强度”第29届土壤工程研究会议摘要集（待提交）（1994年）。