不飽和地盤における各種水理境界変動の影響

各种水力边界变化对非饱和地基的影响

• 批准号: 18760361
• 负责人: 河井 克之
• 金额: $ 2.18万
• 依托单位: Kobe University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18760361/
• 关键词: 地盤工学; 土壌圏現象; 自然災害

自然,人工問わず地盤構造物の多くは土粒子間隙に水と空気を含む三相構造で存在している.間隙が水で満たされている場合を飽和状態と呼び,空気が存在する一般的な不飽和状態とは区別する.しかしながら,地盤工学の発展は飽和状態にある土の挙動を表現することで発展してきたため,未だに不飽和土の力学が実問題へ適用されることは少ない.本研究は,申請者らが究明してきた不飽和土の力学体系を初期値境界値問題として定式化し,実用化するために実現象における各種水理境界変動の解析上の表現法を確立し,その影響を明確にすることを目的としている.前年度,行った土柱試験により地下水位変動と降雨による地盤内含水率変化を実験により求め,解析結果との比較を行った.今年度は,蒸発と外力が地盤内含水率分布に及ぼす影響を検討した.蒸発に関してはモニタリング法という水分特性曲線を求める方法が提案されており,蒸発時の含水率低減とサクション変動が水分保持特性に一致するのは明らかにされている.ここではその影響深度に関して,模型実験と解析の結果を比較した.その結果,地盤表面が乾燥してくると,実蒸発量が低下するため土内部での含水率低下がかなり抑制されることが明らかとなった.また初期の含水率分布によって,地盤のサクション増加挙動が大きく異なることが分かった.外力に関しては,シミュレーションによる検討を行った.非排水条件下で不飽和状態にある地盤に外力を加えると,外力や初期含水状態に依存した,異なる含水率分布を呈することが分かった.この結果は,締固めなどの外部との水収支がない状態で外力が作用する条件で,締固厚さや外力の大きさによって,品質が異なる可能性があることを示唆している.以上,本研究で得られた知見は,不飽和土の力学を地盤工学上の問題へ適用するための一助となったと思われる.今後は,定量的な表現において解析精度を高めていくことを目的とする.

Naturally, the artificial earth structure is composed of many soil particles, water and air, including three-phase structure. In the gap, there is a gap between the status and the status, and there are general conditions and status differences in the air. The performance of the geotechnical exhibition, the geotechnical exhibition and the status of the geotechnical engineering exhibition and the status of the geotechnical engineering exhibition, the geotechnical engineering exhibition and the geotechnical engineering exhibition, the geotechnical engineering exhibition and the geotechnical engineering exhibition. In this study, the applicant demonstrated that the problem of boundary conditions in the early days of the soil mechanics system was formulated, and that the analysis of the movement of various hydraulic boundaries was confirmed by the table method, and it was clear that the purpose of the system was clearly established. In the previous year, the water content in the soil column, the ground water table, the water table, the water content in the soil, the water content in the soil, the water content in the soil column, the ground water table, the water content, the water content, the water content This year, the distribution of moisture content in the soil is affected by external forces. The method of determining the curve of water characteristics is based on the method of determining the curve of water characteristics. the proposed method is suitable for the determination of water retention characteristics in the presence of low moisture content during steaming. The results of the model analysis are compared with the results of the model analysis. The results showed that the surface of the ground was dry and dry, and the amount of steam was low. The water content in the soil was low, and the water content was low. The distribution of water content in the early days of the season is very high, and the distribution of water content in geotechnical and geological areas is very important. The external force is not in the first place, and the external force is not in the line. Under the non-drainage condition, the water content distribution of the water content distribution is divided into two parts: under the non-drainage condition, under the condition of non-drainage, the water content of the external force is increased, the initial water content of the external force is water-dependent, and the water content distribution is divided. According to the results of the test, it is necessary to ensure that the external force acts under the conditions of the external force, the thickness of the external force, the strength of the external force, the possibility and the possibility of the external force. Above, in this study, we have obtained a lot of knowledge and thoughts on geotechnical problems in soil mechanics and soil mechanics. In the future, the quantitative analysis shows that the accuracy of the analysis is high.

项目成果

植生の吸水作用が地盤に及ぼす効果

地面植被吸水的影响

• 发表时间: 2007
• 期刊: 応用力学論文集 10
• 作者: 河井克之;他
• 通讯作者: 他

物質移動を考慮した不飽和土/水連成問題の数理モデルと有限要素解析手法

考虑传质的非饱和土/水耦合问题数学模型及有限元分析方法

• 发表时间: 2006
• 期刊: 応用力学論文集 Vol. 9
• 作者: Katsuyuki Kawai;et. al.;藤川和彦
• 通讯作者: 藤川和彦

Numerical investigation on the failure criterion of normally consolidated clays

正常固结粘土破坏准则的数值研究

• 发表时间: 2006
• 期刊: International Journal for Numerical and Analytical Methods in Geomechanics 562
• 作者: Katsuyuki Kawai;et. al.;藤川和彦;Shinya Tachibana
• 通讯作者: Shinya Tachibana

The salt disaster problem and its mathematical modeling

盐害问题及其数学模型

• 发表时间: 2007
• 期刊: Proc. 3rd Asian Conf. on Unsatruated Soils
• 作者: Atsushi Iizuka;et. al.
• 通讯作者: et. al.

The influences of evapo-transpiration on the ground

蒸散量对地面的影响

• 发表时间: 2007
• 期刊: Proc. 3rd Asian Conf. on Unsatruated Soils
• 作者: Katsuyuki Kawai;et. al.
• 通讯作者: et. al.