Soundness evaluation method and toughening proposition for embankment focussing on soil structure

• Project/Area Number: 18K04356
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22030:Geotechnical engineering-related
• Research Institution: Hachinohe National College of Technology
• Principal Investigator: Kiyohara Yukoh 八戸工業高等専門学校, その他部局等, 准教授 (20369911)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2022: ¥260,000 (Direct Cost: ¥200,000、Indirect Cost: ¥60,000); Fiscal Year 2021: ¥130,000 (Direct Cost: ¥100,000、Indirect Cost: ¥30,000); Fiscal Year 2020: ¥260,000 (Direct Cost: ¥200,000、Indirect Cost: ¥60,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 盛土 / 降雨 / 不飽和浸透 / しらす / 不飽和土 / 水分特性曲線 / 有限要素解析 / せん断 / 繰返し挙動 / 摩耗性 / 不飽和透水係数 / ベントナイト / 透水 / せん断試験 / 繰返し載荷 / 摩耗 / 粒子破砕 / 泥流状崩壊 / 火山灰質土 / 液状化 / 三軸試験 / 細粒分含有率 / 損傷評価 / 間隙構造 / 修復

Outline of Final Research Achievements

Rainfall infiltration behavior and storage capacity on 18 years passed embankment composed of Shirasu soil(volcanic ash sand) were investigated to verify influence of degradation by measuring water content and suction during and after rainfall. The dry density and fine content at a surface area had especially been decreased to small value. By void expansion, water retention capacity had been tended to decrease during these 18 years.
Compressibility and abrasive wear on Shirasu soil particles were also quantified. Then soil-water coupled FEM step by step analyses were performed to clarify the liquefaction process considering those properties. Computer programs for nonlinear elasto-plastic model with kinematic hardening law were made and verified under strain or stress controlled condition.
Permeability and maximum strength on Bentonite mixed Shirasu soil whose fine particle had been lost were improved.

Academic Significance and Societal Importance of the Research Achievements

施工後長期間経過した盛土の降雨時浸透挙動の変化を18年という長期間にわたって計測し，その間の植生変化が保水性，水分特性に及ぼす影響，表層付近での細粒分の流失，間隙比の増加を明らかにした，これは降雨時の浸透挙動，浸潤線の上昇の予測精度を上げることに寄与し，豪雨時の土砂災害ハザードマップ作成の際にも有用な情報源となる．表層付近の空隙を密実化するためのベントナイト粒子の補填実験を室内で行ったところ，透水性の低下回復は顕著であった.また，混入による最大強度が増加したが，せん断定数向上までは期待できなかった．

Research Products

• [Journal Article] Verification of nonlinear calculation method and computer programing for elasto-plastic bilinear hardening model (2021)
  • Author(s): 清原 雄康
  • Journal Title: RESEACH REPORTS National Institute of Technology,Hachinohe College Volume: 55 Issue: 0 Pages: 77-83
  • DOI: 10.24704/hnctech.55.0_77
  • NAID: 130008036109
  • ISSN: 0385-4124, 2433-2003
  • Year and Date: 2021-02-19
  • Open Access
• [Journal Article] Dissipated energy verification on silica sand and volcanic sandy ash soil Shirasu with chemical grouting and compaction under triaxial cyclic behavior (2020)
  • Author(s): 清原雄康
  • Journal Title: Japanese Geotechnical Journal Volume: 15 Issue: 1 Pages: 15-24
  • DOI: 10.3208/jgs.15.15
  • NAID: 130007823102
  • ISSN: 1880-6341
  • Year and Date: 2020-03-31
  • Peer Reviewed / Open Access
• [Journal Article] Evaluation of liquefaction/mudflow resistance of improved volcanic sandy ash soils focusing on dissipated energy (2020)
  • Author(s): Y. KIYOHARA, M. KAZAMA
  • Journal Title: Proceedings of the 17th World Conference on Earthquake Engineering, 17WCEE Sendai, Japan - September 13th to 18th, 4e-0002 Volume: 1 Pages: 1-8
  • Peer Reviewed
• [Journal Article] 基準化累積損失エネルギーによる砂や各種しらす土の繰返し挙動評価 (2019)
  • Author(s): 清原 雄康
  • Journal Title: エネルギーに基づく液状化予測手法に関するシンポジウム論文集 Volume: - Pages: 359-365
• [Journal Article] 飽和田子しらすの単調および繰返しせん断挙動と浸透型薬液による改良効果 (2018)
  • Author(s): 清原 雄康
  • Journal Title: 第61回地盤工学シンポジウム発表論文集 Volume: - Pages: 289-292
  • Peer Reviewed
• [Presentation] 降雨時しらす盛土表層部における雨水の表面流下と浸透挙動 (2022)
  • Author(s): 清原雄康
  • Organizer: 第57回地盤工学研究発表会
• [Presentation] 施工後長期間経過した八戸しらす野外盛土の降雨時浸透特性 (2022)
  • Author(s): 張間 遍・清原雄康
  • Organizer: 令和3年度土木学会東北支部技術研究発表会
• [Presentation] 中空ねじり試験機を用いた低拘束圧下での飽和硅砂7号の繰返し変形特性 (2022)
  • Author(s): 平川巧都・清原雄康
  • Organizer: 令和3年度土木学会東北支部技術研究発表会
• [Presentation] 移動硬化則を用いた弾塑性構成モデルの構築と三軸繰返し挙動の再現解析 (2022)
  • Author(s): 田中茉優・清原雄康
  • Organizer: 令和3年度土木学会東北支部技術研究発表会
• [Presentation] しらす土におけるベントナイトミルク浸透挙動とフィルタリング効果 (2022)
  • Author(s): 清原雄康，中山美優，宮内亘紀
  • Organizer: 令和3年度土木学会東北支部技術研究発表会
• [Presentation] 小型繰返し一面せん断試験装置を用いたしらす土粒子摩耗量の評価 (2021)
  • Author(s): 清原雄康, 長内 涼花
  • Organizer: 第56回地盤工学研究発表会
• [Presentation] Evaluation of liquefaction/mudflow resistance of improved volcanic sandy ash soils focusing on dissipated energy (2021)
  • Author(s): Y. KIYOHARA, M. KAZAMA
  • Organizer: 17WCEE Sendai
  • Int'l Joint Research
• [Presentation] 一軸圧縮試験によるしらす土粒子の圧縮強度と体積弾性係数の評価 (2020)
  • Author(s): 清原雄康,赤坂綾斗
  • Organizer: 第55回地盤工学研究発表会
• [Presentation] 施工後14年経過した八戸しらす盛土の降雨時浸透挙動 (2019)
  • Author(s): 清原雄康，端本蓮，木村匡伯
  • Organizer: 第54回地盤工学研究発表会
• [Presentation] 水分特性曲線を利用した野外盛土の間隙径推測と劣化度評価 (2019)
  • Author(s): 端本蓮，清原雄康
  • Organizer: 第54回地盤工学研究発表会
• [Presentation] 基準化累積損失エネルギーによる砂や各種しらす土の繰返し挙動評価 (2019)
  • Author(s): 清原 雄康
  • Organizer: エネルギーに基づく液状化予測手法に関するシンポジウム
• [Presentation] ベントナイト15%混合八戸しらす土のせん断強度特性 (2018)
  • Author(s): 清原 雄康
  • Organizer: 土木学会東北支部技術研究発表会（平成30年度）
• [Presentation] 低飽和度下における二戸しらすの繰返し挙動に及ぼす飽和度の影響 (2018)
  • Author(s): 粒来 真優子
  • Organizer: 土木学会東北支部技術研究発表会（平成30年度）
• [Presentation] 不飽和硅砂７号の非排気繰返しせん断挙動と累積損失エネルギー (2018)
  • Author(s): 清原 雄康
  • Organizer: 第53回地盤工学研究発表会
• [Presentation] 降雨時・地震時における地盤の挙動と防災 (2018)
  • Author(s): 清原 雄康
  • Organizer: 1968年十勝沖地震50周年シンポジウム－過去を見つめこれからを考える－
  • Invited
• [Remarks] research map 清原雄康
  • URL: https://researchmap.jp/read0205010/
• [Patent(Industrial Property Rights)] 三軸圧縮試験方法及び三軸圧縮試験装置 (2018)
  • Inventor(s): 清原 雄康
  • Industrial Property Rights Holder: 清原 雄康
  • Industrial Property Rights Type: 特許
  • Filing Date: 2018