Published 2018 | Version v1
Journal article Metadata-only

Discussion on water migration and swelling of compacted powder bentonites

Creators

  • 1. Waseda Univ., Faculty of Science and Engineering, Tokyo (Japan)
  • 2. Iwate Prefectural Government, Morioka, Iwate (Japan)
  • 3. Waseda Univ., Graduate School of Creative Science and Engineering, Tokyo (Japan)
  • 4. Taisei Corp., Nuclear Facilities Division, Tokyo (Japan)

Description

Bentonite based buffer will change its condition from unsaturated state to saturation by groundwater seepage in high level radioactive waste disposal facility. This study has investigated water migration and swelling pressure characteristics in bentonite based buffer from unsaturated state to saturation from the viewpoint of material specifications such as kinds of bentonite and dry density. From the experimental results in this study, water migration behaviors in various powder bentonites as buffer have an analogy to water-diffusion from initial water content to around 90% saturation. Furthermore, the inflection points have appeared at around 90% saturation in the relationships between swelling-pressure and elapsed time. Therefore, the factor dominating water migration in buffer will change according to alternation of micro-structure in bentonite based buffers by swelling. (author)

Availability note (English)

Available from https://doi.org/10.2208/jscejge.74.63

Abstract (Japanese)

高レベル放射性廃棄物地層処分の地下施設におけるベントナイト系緩衝材は,地下水の浸入に伴い不飽和から飽和へと遷移する.本研究では,ベントナイトの種類や乾燥密度等の材料仕様の観点から,不飽和から飽和に至る過程の水分移動と膨潤圧挙動との関係について,国内外の粉体状ベントナイト各種を用いて実験的に調査した.その結果,吸水開始から飽和度90%程度の範囲で水分移動は拡散的な挙動と見なせることを示した.また,飽和度90%程度の時点で膨潤圧の発生挙動に変曲点が認められ,膨潤に伴う緩衝材中の構造的な変化に起因して,水分移動の支配的な要因が変化したと考察した.(著者)

Additional details

Additional titles

Original title (Japanese)
締固めた粉体状ベントナイト各種の水分移動特性と膨潤圧挙動に関する考察

Identifiers

DOI
10.2208/jscejge.74.63;

Publishing Information

Journal Title
Doboku Gakkai Ronbunshu C. Chiken Kougaku
Journal Volume
74
Journal Issue
1
Series
雑誌名:土木学会論文集C (地圏工学)
Journal Page Range
p. 63-75
ISSN
2185-6516

INIS

Country of Publication
Japan
Country of Input or Organization
Japan
INIS RN
51044373
Subject category
S12: MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES;
Descriptors DEI
BENTONITE; DARCY LAW; DIFFUSION BARRIERS; GROUND WATER; HIGH-LEVEL RADIOACTIVE WASTES; HUMIDITY; ION EXCHANGE; MONTMORILLONITE; PERMEABILITY; PERMIAN BASIN; RADIOACTIVE WASTE DISPOSAL; SWELLING; UNDERGROUND DISPOSAL; UNDERGROUND FACILITIES
Descriptors DEC
CLAYS; DEFORMATION; HYDROGEN COMPOUNDS; INORGANIC ION EXCHANGERS; ION EXCHANGE MATERIALS; MANAGEMENT; MATERIALS; MINERALS; MOISTURE; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; RADIOACTIVE MATERIALS; RADIOACTIVE WASTE MANAGEMENT; RADIOACTIVE WASTES; SILICATE MINERALS; WASTE DISPOSAL; WASTE MANAGEMENT; WASTES; WATER

Optional Information

Notes
30 refs., 11 figs., 4 tabs.