• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1994 Fiscal Year Final Research Report Summary

Study on effective protiction works by stones or gravel against local scour of sand bed

Research Project

Project/Area Number 05650495
Research Category

Grant-in-Aid for General Scientific Research (C)

Allocation TypeSingle-year Grants
Research Field 水工水理学
Research InstitutionEhime University

Principal Investigator

SUZUKI Koichi  Ehime Univ., Dept.of Civil & Ocean Eng., Dr.Eng., Professor, 工学部, 教授 (70026285)

Co-Investigator(Kenkyū-buntansha) KURIHARA Takashi  Ehime Univ., Dept.of Civil & Ocean Eng., Ms.Eng., Research Associate, 工学部, 助手 (70243805)
WATANABE Masahiro  Ehime Univ., Dept.of Civil & Ocean Eng., Dr.Eng., Asociate Professor, 工学部, 助教授 (70036458)
Project Period (FY) 1993 – 1994
Keywordssand-gravel mixture / sorting of sediment / flow resistance / mountain river / stair-like bed form / bed protection by gravel / armor coat / filter effect
Research Abstract

There are some hydraulic phenomena specific to the river bed with mixture of sand, gravel and stone such as armor coat formation or stair like bed form. Here two phenomena are studied : 1) conditions for effective protection works by stones or gravel against local scour of sand bed, and 2) flow resistance and bed form with transverse limb in mountain rivers. Main results are as folloes ;
1) Protection works by stones or gravel against local scour of sand bed around river structures are effective only if the protected bed sand is not drawn out through the cover layr of stones or gravel which is stable against tractive force by the local flow. Hydraulic conditions for the effective protection works are studied experimentally. Bed sand can not geometrically move through the stones or gravel layr, when the ratio, D/d, of stones or gravel scale D to sand scale d is less than 2. The tractive force on the bed sand is exponentially reduced through the protection layr as a function of the ratio, L/D,of the protection layr thickness L to D.
2) Flow resistance and bed form with trasverse limb are discussed with data observed in a mountain river and obtained by experiments for the bed with sand-gravel mixture or fixed crosspiece roughness. The ratio, lambda/DELTA, of wave length lambda to wave high DELTA of limb bed in mountain rivers is about 10, in which case flow resistance is proved to become maximum by experiments. Flow resistance on the bed with relatively large roughness changes largely according to the flow patterns, and it becomes largestwhen the ratio, h_m/DELTA, of flow depth h_m to the roughness height DELTA is about 1.7 for lambda/DELTA=10

  • Research Products

    (12 results)

All Other

All Publications (12 results)

  • [Publications] Suzuki,K: "Grain Sorting of sediment" Jour.Hydroscience and Hydraulic Engineering. SI-2. 57-77 (1993)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Suzuki,K.: "Field study on debris and sediment flows in a small mountain torrent" Proc.25 Congress,IAHR. B. 102-108 (1993)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 鈴木幸一: "二粒径混合砂礫による流砂量に及ぼす砂礫の混合効果" 水工学論文集. 38. 627-632 (1994)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Suzuki,K.: "Discharge of gravel on the bed with sand-gravel mixtures" Proc.9th Congress,APD-IAHR. 2. 313-319 (1994)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 鈴木幸一: "局所洗掘防止に有効な石礫護床工の条件" 水工学論文集. 39. (1995)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 鈴木幸一: "山地河道のリブ河床形態と流水抵抗に関する研究" 水工学論文集. 39. (1995)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Suzuki, K.: "Grain sorting of sediment" Jour.Hydroscience and Hydraulic Eng.SI-2. 57-77 (1993)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Suzuki, K.Watanabe, M.Kurihara, T.Segawa, T.: "Field study on debris and sediment flows in a small mountain torrent" Proc.25 Congrees, IAHR. B. 102-108 (1993)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Suzuki, K.Kurihara, T.Yamamoto, H.: "Study on mixing effects on sediment discharge of sand and gravel with uniform grain size" Proc.Hydraulic Eng., JSCE. 38. 627-632 (1994)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Suzuki, K.Kurihara, T.Yamamoto, H.: "Discharge of gravel on the bed with sand-gravel mixtures" Proc.9th Congress, APD-IAHR. 2. 313-319 (1994)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Suzuki, K.Yamamoto, H.Kurihara, T.: "Conditions for effective protection works by stones or gravel against local scour of sand bed" Proc.Hydraulic Eng., JSCE. 39. (1995)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Suzuki, K.Kurihara, T.Yamamoto, H.: "Flow resistance and bed form with traverse limb in mountain rivers" Proc.Hydraulic Eng., JSCE. 39. (1995)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 1996-04-15  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi