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

Strength and deformation of rocks under freezing condition and their fracture mechanism

Research Project

Project/Area Number 17560720
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Earth system and resources enginnering
Research InstitutionHokkaido University (2006-2007)
Muroran Institute of Technology (2005)

Principal Investigator

KODAMA Jun-Ichi  Hokkaido University, Grad. School of Eng., Associate Professor (70241411)

Project Period (FY) 2005 – 2007
Project Status Completed (Fiscal Year 2007)
Budget Amount *help
¥3,540,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥240,000)
Fiscal Year 2007: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2006: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 2005: ¥1,900,000 (Direct Cost: ¥1,900,000)
KeywordsRock / Freezing condition / Strength / Deformation / Fracture process / Inclusion model / 破壊メカニズム / インクリージョンモデル / 安山岩 / 凍結 / 一軸圧縮強度 / 圧裂引張強度 / 含水飽和 / 温度 / 載荷速度 / 圧縮強度 / 引張強度 / 含水比
Research Abstract

Uniaxial compression tests and Brazilian tests were carried out to clarify mechanical behaviors and fracture mechanism of rocks under freezing condition. Effect of water content on strength and deformation was investigated and fracture process of the frozen rock was elucidated based on deformation behaviors and AE activities. Effects of temperature and loading rate on strength and deformation were also examined. Experimental results were discussed on the basis of an inclusion model considering mechanical role of ice within the rock. Main results are as follows.
(1) At dry condition, micro-fracturing increased exponentially just before strength failure and brittle rupture was observed. At water saturated condition, specimen deformed elastically up to high stress level and occurrence of micro-fracture increased at a constant rate prior to strength failure.
(2) Strength, critical strain and Poisson's ratio increased with increase in water content at -20 degrees C. Strength increased, but critical strain, Young's modulus and Poisson's ratio were not changed with rise in temperature between -5 degree C and -20 degree C. Strength increased with loading rate, at -20 degree C, but critical strain, Young's modulus and Poisson's ratio were not affected by loading rate.
(3) Based on the inclusion mode], it was found that stress concentration near the tip of crack is reduced if Young's modulus of ice increases Young's modulus of ice was cleared to increase with drop in temperature or increase in loading rate through previous studies. Strength of frozen rock can be estimated to increases with drop in temperature or increase in loading rate because stress at fracture initiation increase with them.

Report

(4 results)
  • 2007 Annual Research Report   Final Research Report Summary
  • 2006 Annual Research Report
  • 2005 Annual Research Report
  • Research Products

    (6 results)

All 2007

All Presentation (6 results)

  • [Presentation] 凍結融解下における岩石内部き裂の進展量に関する基礎的研究2007

    • Author(s)
      児玉淳一
    • Organizer
      開発技術研究会
    • Place of Presentation
      室蘭工業大学(室蘭)
    • Year and Date
      2007-12-07
    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2007 Annual Research Report 2007 Final Research Report Summary
  • [Presentation] Crack growth in rocks subjected to freezing and thawing cycles2007

    • Author(s)
      KODAMA, Jun-ichi
    • Organizer
      The association of innovative technology annual meeting
    • Place of Presentation
      Muroran Institute of technology (Muroran)
    • Year and Date
      2007-12-07
    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2007 Final Research Report Summary
  • [Presentation] 凍結融解作用を受ける岩石のき裂進展量の計測2007

    • Author(s)
      児玉淳一
    • Organizer
      資源・素材2007
    • Place of Presentation
      名古屋大学(名古屋)
    • Year and Date
      2007-09-27
    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2007 Final Research Report Summary
  • [Presentation] Measurement of crack length in rocks subjected to freezing and thawing cycles2007

    • Author(s)
      KODAMA, Jun-ichi
    • Organizer
      MMIJ fall meeting
    • Place of Presentation
      Nagoya university (Nagoya)
    • Year and Date
      2007-09-27
    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2007 Final Research Report Summary
  • [Presentation] 凍結融解作用を受けた登別溶結凝灰岩の表面および内部観察2007

    • Author(s)
      児玉淳一
    • Organizer
      資源・素材学会春季大会
    • Place of Presentation
      早稲田大学理工学部(東京)
    • Year and Date
      2007-03-31
    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2007 Final Research Report Summary
  • [Presentation] Observation of Noboribetsu welded tuff subjected to freezing and thawing cycles2007

    • Author(s)
      KODAMA, Jun-ichi
    • Organizer
      MMIJ spring meeting
    • Place of Presentation
      Waseda university(Tokyo)
    • Year and Date
      2007-03-31
    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2007 Final Research Report Summary

URL: 

Published: 2005-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi