Evaluation of hydraulic properties of unsaturated soils considering bulk density

考虑容重的非饱和土水力特性评价

• 批准号: 11650515
• 负责人: YAMADA Kimio
• 金额: $ 2.43万
• 依托单位: Chubu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650515/
• 关键词: Unsaturated soils; Hydraulic conductivity of Unsaturated Soils; Soil water characteristic curves; Suction; Void Ratio; Unsteady state method; Silty sand; Approximated Profile method; 乾燥密度

(1) Method of measuring the bulk density of soils was developed during the phychrometer method. Therefore, soil water characteristic curves could be obtained considering void ratio over the full range of degree of saturation.(2) A new model of soil water characteristic curve could be formulated for silty sand. It can be presented the behavior of void ratio, saturation and matric suction of silty sand. And we got that it is applicable to other silts.(3) It was found that Matric suction in the shrinkage limit was concerned with the initial wilty point.(4) An experiment method has been developed to estimate the permeability of unsaturated soils. It is an improved type of the original instantaneous profile method, and is able to measure the permeability of many kinds of soils. The new method is characterized by the unsteady condition of water profile and linear approximation of moisture distribution.(5) Volume change of the specimen affects the measured, therefore, we corrected the volume of the specimen by the water retention curves considering bulk density. This proposed method could measure the hydraulic conductivity of unsaturated soils taking account of the considerable volume change.(6) The relationship between compaction energy and pore water pressure is investigated through laboratory testing. And then, the behavior of suction could be explained by the distance between interacting particles.

(1)土壤容重的测定方法是在物理仪法的基础上发展起来的。因此，考虑孔隙比可以得到整个饱和度范围内的土壤水分特征曲线。(2)提出了一种新的粉质砂土土壤水分特征曲线模型。它可以反映粉质砂土的孔隙比、饱和度和基质吸力的特性。并得出该方法适用于其它粉土的结论。(3)发现收缩极限内的基质吸力与初始软化点有关。(4)提出了一种估算非饱和土渗透系数的试验方法。该方法是对原有瞬时剖面法的改进，能测定多种土壤的渗透性。新方法的特点是水分剖面的非稳态条件和水分分布的线性近似。(5)试样的体积变化对测量结果有一定的影响，因此，考虑到体积密度的影响，用保水曲线对试样的体积进行了修正。该方法可以测量非饱和土的导水率，同时考虑到体积的变化。(6)通过室内试验，研究了压实能与孔隙水压力的关系。然后，吸力的行为可以用相互作用粒子之间的距离来解释。

项目成果

T.Sugii, K.Yamada, and H.Kondo: "Estimation of water retention curves of sandy soils by use of compaction energy"Memoirs of College of Engineering, Chubu University. Vol.36. 62-70 (2000)

T.Sugii、K.Yamada 和 H.Kondo：“利用压实能估算沙土保水曲线”中部大学工学院回忆录。

杉井俊夫: "締固めエネルギーを用いた砂質土の水分保持特性の評価に関する研究"中部大学工学部紀要. 第36巻. 15-24 (2000)

Toshio Sugii：“利用压实能量评估沙土保水性能的研究”中部大学工学部通报第 36 卷 15-24（2000 年）。

山田公夫: "砂の水分特性曲線の推定に関する研究"土木学会第54回年次学術講演概要集第3部(A). 590-591 (1999)

Kimio Yamada：“砂土湿度特性曲线估计的研究”第54届日本土木工程学会学术讲座摘要第3部分（A）590-591（1999）。

Toshio Sugii: "Permeability test of unsaturated soil approximating moisture distribution"Proc. of Int'l Symp.on Suction,Swelling,Permeability and Structure of Clay. 303-309 (2001)

Toshio Sugii：“近似水分分布的非饱和土的渗透性试验”Proc。

T.Sugii, K.Yamada, M.Uemura, T.Okumura and T.Saso: "Approximated profile method for hydraulic conductivity test of unsaturated soils."Proc.of Symposium on Geotechnical Engineering in the Chubu branch of JGS. 7-14 (2000)

T.Sugii、K.Yamada、M.Uemura、T.Okumura 和 T.Saso：“非饱和土导水率测试的近似剖面法”。JGS 中部分会岩土工程研讨会论文集。