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Creep Characteristics of Rocks and Concrete - A Comparison

암(岩)과 콘크리트의 Creep 특성에 대한 비교평가
Hak-Moon Kim1
김 학문1
1단국대학교 토목공학과 교수

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ABSTRACT

It is well known fact that all rocks exhibit brittle properties and time depends strain properties (creep). An understanding of the time dependent deformation behaviour of rocks is believed to be essential in the field of civil and tunnelling. The rock and concrete creep in various forms of loading conditions and physical environment are reviewed. A comparison of creep behaviour between rocks and concrete is provided, in order to bring two existing relatively independent methods of predicting creep strain closer together. It was felt that the physical process in the creep of rocks would be similar to the process in creep of concrete. Since experiments and observations have shown that non-elastic (creep) mechanical behaviour of all crystalline solids (i.e., concrete, rocks, ceramics and refractories) and single materials have a common base. Also a comparison of the results for the accepted methods of estimating creep in rocks and concrete under - multiaxial loading was attempted to extend the knowledge of deformational characteristics of these two materials.

Keywords
Rock Creep
Concrete Creep
Creep Strain
Test Method
Physical environment
Comparison

모든 암석들이 취성이나 시간변형거동인 Creep 특성을 나타낸다는 것은 잘 알려진 사실이다. 암석들에 대한 시간변형거동의 이해는 토목이나 터널기술분야에 필수적인 요건이 된다. 그러므로 다양한 하중조건과 물리적 환경사태에서 암석과 콘크리트에 대한 Creep 특성을 조사하였다. 두가지 다른 Creep변형예측공식을 사용하여 그 결과를 비교함으로서 이들 재료들의 유사점을 찾아보았다. Creep 변형예측공식을 사용하여 3축압축 상태에서 얻어진 실험결과들과 비교 평가하였다.

키워드
암의 Creep
콘크리트의 Creep
Creep 변형
실험방법
물리적환경
비교평가

MAIN

  • 1. Introduction

  • 2.Brief Review of Rock and Concrete Creep

  •   2.1 Creep Nature of Rock

  •   2.2 Measure of Rock Creep in Laboratory

  •   2.2.1 Triaxial Creep Tests

  •   2.3 Measurement of Concrete Creep

  •   2.3.1 Mathematical Models and Their Mechanisms for Concrete

  • 3. Physical Environmental Effects on Rock Creep

  •   3.1 Influence of Temperature

  •   3.1.1 Creep Theories Influence of Temperature

  •   3.1.2 Experimental Results

  •   3.2 Effects of Water and Other Solutions

  •   3.2.1 Experimental Results

  •   3.3 Specimen Shape and Size Effects

  •   3.4 Effect of Confinement

  • 4. Major Influencing Facts of Creep Behavior in Concrete

  •   4.1 The Relative Volume Ratio of the Aggre gate to Cement Paste

  •   4.2 The Stiffness Effect of Aggregate

  •   4.3 Type of Cement

  •   4.4 Water / Cement Ratio

  •   4.5 Age of Concrete at Loading

  •   4.6 The Effect of Relative Humidity

  •   4.7 Temperature Effects

  •   4.8 Size of Concrete Member (or Specimen)

  • 5. Prediction of Concrete Creep and Their Measurements

  •   5.1 The Logarithmic Law

  •   5.2 Uniaxial Compression Test

  •   5.3 Uniaxial Tensile Creep Test

  •   5.4 Triaxial Compression Creep Test

  • 6. Conclusions

  •   6.1 Behavior and Measurement of Creep

  •   6.2 Behavior and Measurement of Creep in Concrete

Acknowledgements

References

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