Research on ground characteristics of permafrost in Mongolia

蒙古国多年冻土地面特征研究

• 批准号: 15404014
• 负责人: ONO Koichi
• 金额: $ 4.8万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 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-15404014/
• 关键词: frost heave; differential settlement; permafrost; Mongolia; pipeline; 融解沈下

During the first year measurement site is set on the designated area to measure seasonal frost heaves in Mongolian ground. Based on the measurement from Oct.2003 to Oct.2004, the following conclusions are obtained :1)large heaves are observed in the ground with high water level, regardless of permafrost's existence.2)Susceptible ground such as clay can yield large heave, while unsusceptible ground such as sand can yield small heave. However, the ground of sand in lower layer and clay in upper layer also can yield much heave because sand layer may promote suction of water to form ice lens in clay layer.3)Slow freezing speed gives large heave.On the other hand, laboratory test on the samples taken from the site is conducted to define frost heave ratio and other parameters in Takashi equation. As a result, it is found that heave of the ground strongly depends on freezing speed. Additionally from the sensitivity analysis for the Takashi equation, it is also found that over load and freezing speed are dominant parameters in the equation.Finally, it can be said that the frost heave estimation can be done by conducting laboratory test on the samples in site, and this fact can be applied to the pipeline design in permafrost area.

在第一年，在指定的地区设置测量点，测量蒙古国地面的季节性霜冻。根据2003年10月至2004年10月的实测结果，得出以下结论：（1）在高水位条件下，无论有无多年冻土，地基都会产生较大的隆起;（2）粘性土等敏感地基会产生较大的隆起，而砂土等非敏感地基会产生较小的隆起。但是，由于砂层会促进水的吸入，在粘土层中形成冰透镜，下层砂层和上层粘土层的地基也会产生较大的隆起。3）冻结速度慢，引起较大的隆起。另一方面，对现场取样进行室内试验，确定了Takashi方程中的冻胀率等参数。结果表明，冻结速度对土体的隆起有很大的影响。通过对Takashi方程的敏感性分析，发现超载和冻结速度是该方程的主导参数，可以通过现场的室内试验来估算冻土区的冻胀量，这一点可以应用于多年冻土区的管道设计。

项目成果

Frost heave and thaw settlement monitoring in Mongolia for pipeline design

蒙古管道设计中的冻胀和融沉监测

• 发表时间: 2003
• 期刊: Proc.of the 16th KKCNN sym.on Civil Eng., Korea
• 作者: L.Sukhubyan;K.Ono;Y.Oshima
• 通讯作者: Y.Oshima

Design for a pipeline monitoring using fiber optic sensors

使用光纤传感器进行管道监测的设计

• 发表时间: 2003
• 期刊: Proc.of structural health monitoring and intelligent infrastructure
• 作者: Y.Oshima;K.ONO;K.Sugiura
• 通讯作者: K.Sugiura

Ground behavior in permafrost area of Mongolia

蒙古多年冻土区的地面行为

• 发表时间: 2004
• 期刊: Proc.of the 17th KKCNN sym.on Civil Eng.
• 作者: Y.Oshima;K.Ono;L.Sukhbuyan
• 通讯作者: L.Sukhbuyan