ため池コア材への旧堤体土・底泥土再利用に関する一考察 : 兵庫県下における老朽化ため池を事例として  [in Japanese] Muddy Soil and Old Banking Material Reuse Technique for the Core Zone of Small Earth-fill Dams : A case study of aging small earth-fill dam in Hyogo Prefecture  [in Japanese]

Access this Article

Search this Article

Author(s)

Abstract

全国に21万個,兵庫県に4万個以上あるため池の多くが老朽化という問題を抱えており,地震や台風などによって大きな被害を受けている.そこで早急な改修が必要であるが,ため池改修を実施する上で,適切なコア用土の確保が現在の課題として存在する.また,築造年代が古く老朽化したため池には,池底に汚泥が堆積しており,悪臭や貯水量低下の原因となっている.そこで,本研究では,環境に優しく安価で力学的に安定したコア用土を得るために,現場発生土である底泥土と旧堤体盛土材の再利用を検討した.底泥土と旧堤体盛土材の適切なブレンド割合を明らかにするために,混合土に対して一軸圧縮試験と透水試験を実施するとともに,生石灰や産業廃棄物であるフライアッシュの有用性を検討した.また,現場適用を考慮し,大型混練機による現場試験を実施し混合土のバラツキを評価した.各実験の結果,底泥土と旧堤体盛土材の混合土はため池コア用土として十分な強度と遮水性を有し,再利用の可能性が示唆された.

Japan has 210,000 earth-fill dams and many of them are located in the Hyogo prefecture. These earth-fill dams were constructed over a long period of history, and damaged by earthquakes and typhoons. However, under reconstruction, there is a problem which is lack of suitable soil material for the core zone. Further, old earth-fill dams have large deposit of muddy soil. <br>In this paper, a method of creation of improved soil for impermeable core zone was proposed. The method was used some materials that should be recycled, for example muddy soil and old banking material. It is necessary to be said that the material is not only low cost but also mechanically stability and environmentally-friendly. In the laboratory, unconfined compression test and permeability test were conducted to clarify the best mixture fraction, and availability of quicklime and fly ash. Additionally, the field test was conducted. A large soil mixing machine was used to blend these materials, and it was tested for practical applicability since the improved soil for the impermeable core zone needs to be homogeneously-mixed. As the result of laboratory and field experiments, the improved soil made of muddy soil and old banking material had sufficient strength and impermeability. It was suggested that the improved soil could be reused when earth-fill dams were reconstructed.

Journal

  • Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering

    Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering 81(2), 171-176, 2013-04-25

    The Japanese Society of Irrigation, Drainage and Rural Engineering

References:  12

Codes

  • NII Article ID (NAID)
    10031171488
  • NII NACSIS-CAT ID (NCID)
    AA12240517
  • Text Lang
    JPN
  • Article Type
    ART
  • ISSN
    18822789
  • Data Source
    CJP  J-STAGE 
Page Top