Article Factors Controlling Salt Susceptibility and Alteration Indices on Salt Weathering of Oolitic Limestone Using Single Salt at Five Weathering Regimes, a Case Study was published on December 1, 2013 in the journal Restoration of Buildings and Monuments (volume 19, issue 6).

Soil production function

10.1515/rbm-2013-6625

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Citations (2)

Fundamental Study on Flow Resistance in Rock Fissures

SOILS AND FOUNDATIONS (1984)

Kuniaki Sato Kunio Watanabe Nobuyoshi Kotajima

Fissure

10.3208/sandf1972.24.1

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Citations (6)

Analysis of the Transient Temperature Change in Fractured Rock Mass during the In-situ Freezing and Thawing Test.

Journal of the Japan Society of Engineering Geology (1996)

Koji Ishiyama Kunio Watanabe Tadashi Yamabe Toshi Nomoto

A large scale in-situ freezing and thawing test was carried out in a tunnel of the Kamaishi Mine to understand the conduction of heat in a fractured rock mass. Nine freezing pipes of 2.5m long were installed in nine boreholes drilled from the tunnel floor. The brine liquid was circulated through those pipes in order to freeze the rock mass of the test site. The temperature of the brine was flxed at -20°C and the circulation of the brine liquid was continued for 7-10 days in each freezing process. Thawing process was conducted by stopping the circulation after each freezing process. The duration of thawing process was about 1 month. The transient change of the temperature around those pipes was continuously measured in 23 observation holes at depths of 1m, 2m, 3m, respectively.The temperature distributions around the freezing pipes were calculated by three dimensional finite element analysis using homogeneous continuum assumptions. The latent heat of water, contained in the rock mass and the heat transfer from the tunnel floor were taken into account in the analysis. The calculated temperature changes were compared with the measured ones.The conclusions obtained are summarized as follows.(1) The change of the temperature is infiuenced considerably by the latent heat of water when a phase change of water occurred in the rock mass.(2) Thickness of thermal boundary layer, induced by heat transfer from the tunnel floor, is evaluated as 1-3cm in the analysis.(3) The temperature distributions in the fractured rock mass can be estimated by the assumption that the rock mass is homogeneous continuum.

Brine

Mass concrete

10.5110/jjseg.37.84

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Observation of ice lensing in glass-powder medium. The relationship between ice lens Growth and water content.

Journal of the Japanese Society of Snow and Ice (2001)

Yoshiko Muto Kunio Watanabe Takeshi Ishizaki Masaru Mizoguchi

アイスレンズの成長面付近の水分状態とアイスレンズの厚みの関係を調べるために,水で飽和したガラス多孔質体中に析出するアイスレンズを観察する実験を行った.ガラス多孔質体の凍結速度と温度勾配は,一方向凍結装置を用いて一定に制御した.まず,初期含水比が異なるガラス多孔質体中に析出したアイスレンズの厚みを比較した.その結果,初期含水比が高いほどアイスレンズが厚く成長することがわかった.次に,凍結過程のガラス多孔質体の未凍結領域において,含水比分布を数mm間隔で測定した.その結果,アイスレンズの成長面から高温側には,異なる2種の含水比領域が生じることがわかった.アイスレンズの成長によらず,成長面より約20mm以遠の含水比は初期含水比を維持した.成長面近傍から約20mmの領域の含水比は初期含水比より低く,またアイスレンズが厚く成長した場合ほど低かった.この結果は,アイスレンズが発生してから成長を終えるまでの,成長面付近の含水比の変化を示していると考えられる.

10.5331/seppyo.63.3

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Freezing experiments on unsaturated sand, loam and silt loam

Annals of Glaciology (2011)

Kunio Watanabe Tetsuya Kito Tomomi Wake Masaru Sakai

Abstarct Estimating soil-water flow during ground freezing is important for understanding factors affecting spring farming, soil microbial activity below the frozen soil, and permafrost thawing behavior. In this study, we performed a column freezing experiment using three different unsaturated soils (sand, loam and silt loam) to obtain a detailed dataset of temperature, water-content and pressure-head change under freezing conditions. The liquid water content and pressure head in the three soils decreased with decreasing temperature. Three soil temperature stages were found: unfrozen, stagnating near 0˚C and frozen. The temperature and duration of the stagnation stage differed among the soil types. The changes in liquid water content and pressure head during the freezing process were highly dependent on the soil-water retention curve. Water flowed through the frozen area in silt loam and sand, but no water flux was observed in the frozen loam. The freezing soil columns tended to contain more liquid water than estimated from retention curves measured at room temperature, especially at the early stage of freezing.

Silt

Pressure head

10.3189/172756411797252220

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Analysis of hydraulic pressure fluctuation in deep geologic formations in Tono area, Japan using artificial neural networks

Journal of Hydrology (2003)

Mahesh Gautam Kunio Watanabe Hiromitsu Saegusa

Hydraulic pressure

10.1016/j.jhydrol.2003.08.016

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In situ hydraulic tests in the active fault survey tunnel, Kamioka Mine, excavated through the active Mozumi‐Sukenobu Fault zone and their hydrogeological significance

Island Arc (2006)

Tsuyoshi Nohara Hidemi Tanaka Kunio Watanabe Noboru Furukawa Akiyoshi Takami

Abstract The spatial hydrogeological and structural character of the active Mozumi‐Sukenobu Fault (MSF) was investigated along a survey tunnel excavated through the MSF in the Kamioka Mine, central Japan. Major groundwater conduits on both sides of the MSF are recognized. One is considered to be a subvertical conduit between the tunnel and the surface, and the other is estimated to be a major reservoir of old meteoric water alongside the MSF. Our studies indicate that part of the MSF is a sub‐vertical continuous barrier that obstructs younger meteoric water observed in the south‐eastern part of the Active Fault Survey Tunnel (AFST) and water recharge to the rock mass intersected by the north‐western part of the AFST. The MSF might be a continuous barrier resulting in the storage of a large quantity of older groundwater to the northwest. The observations and results of in situ hydraulic tests indicate that the major reservoir is not the fault breccia associated with the northeast–southwest trending faults of the MSF, but the zone in which blocks of fractured rocks occur beside high angle faults corresponding to X shears whose tectonic stress field coincides with the present regional stress field and antithetic Riedel shears of the MSF. The results from borehole investigations in the AFST indicate that secondary porosity is developed in the major reservoir due to the destruction of filling minerals and fracture development beside these shears. The increase in hydraulic conductivity is not directly related to increased density of fractures around the MSF. Development of secondary porosity could cause the increase in hydraulic conductivity around the MSF. Our results suggest that minor conduits of the fracture network are sporadically distributed in the sedimentary rocks around the MSF in the AFST.

Breccia

10.1111/j.1440-1738.2006.00548.x

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Citations (4)

Chapter 1 Fault activity and earthquake proof design—Preface

Developments in geotechnical engineering (1997)

Yuji Kanaori Kunio Watanabe

Earthquake simulation

10.1016/s0165-1250(97)80002-8

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