Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Komatsu, Mitsuru*; Nishigaki, Makoto*; Seno, Shoji*; Hirata, Yoichi*; Takenobu, Kazuyoshi*; Tagishi, Hirotaka*; Kunimaru, Takanori; Maekawa, Keisuke; Yamamoto, Yoichi; Toida, Masaru*; et al.
JAEA-Research 2012-001, 77 Pages, 2012/09
This research focused on methods of estimating the amounts of groundwater recharge, which are normally required as upper boundary conditions in groundwater flow analyses, based on measurements of infiltrating water in the ground, to systematize the methods and establish systems which are stable and measurable on site over a long time. Regarding developing measurement systems, fiber-optic strain measurement methods that enable multiple-point and long-distance measurement were used for measuring three quantities: suction pressure, soil moisture and volumetric water content rate obtained by applying water absorption swelling material, and each measurement was discussed. The results showed that the fiber-optic soil aquameter has two types of practical application: one for measuring suction pressure (Type I), and the other for measuring volumetric water content rate obtained by applying water absorption swelling material (Type III). Furthermore, by using measurement instruments in actual fields, the validity of the two methods for estimating the rainfall infiltration capacities of shallow-layer soils, that is, estimating the capacities either directly by measurements of soil water or from unsaturated hydraulic conductivities, was confirmed.
Komatsu, Mitsuru*; Nishigaki, Makoto*; Seno, Shoji*; Toida, Masaru*; Tagishi, Hirotaka*; Takenobu, Kazuyoshi*; Yamamoto, Yoichi
Chikasui Jiban Kankyo Ni Kansuru Shimpojium 2011 Happyo Rombunshu (CD-ROM), p.17 - 26, 2011/11
no abstracts in English
Komatsu, Mitsuru*; Nishigaki, Makoto*; Seno, Shoji*; Tagishi, Hirotaka*; Takenobu, Kazuyoshi*; Kishi, Atsuyasu
no journal, ,
Infiltration rate at the ground surface is one of the essential boundary conditions for a quantitative evaluation of groundwater flow. Conventional method for quantifying infiltration rate based on the water budget, however, includes significant uncertainties resulting from different types of quantities to be measured. In this study, focusing on a method where the infiltration rate is estimated directly from temporal changes in soil water contents in the region of interest, the measurement data was confirmed based on the unsaturated hydraulic tests. Then, the reliability of the measurement was verified by comparing the data to the laboratory test results and uncertainties associated with the measurements were quantified.
Seno, Shoji*; Komatsu, Mitsuru*; Nishigaki, Makoto*; Tagishi, Hirotaka*; Takenobu, Kazuyoshi*; Kishi, Atsuyasu
no journal, ,
The soil moisture measurement method is being developed with the application of the optical fiber sensor, that is thought to be more advantageous than the conventional methods in the soil moisture measurement regarding its characteristics of multiple-point and long-distance measurement. We report the results obtained in the performance test of the optical fiber moisture metering sensor in the course where its fundamental mechanism and its principle are being developed.