[논문]점성토에 있어서의 크리프 거동 예측

김대규

점성토에 있어서의 크리프 거동 예측
Prediction of Creep Behavior for Cohesive Soils 원문보기

韓國地盤工學會論文集 = Journal of the Korean geotechnical society, v.20 no.7, 2004년, pp.79 - 89

김대규 (Dept. of Civil and Environ. Engrg. Sang-Myung Univ.)

초록
AI-Helper

본 연구에서는 탄.소.점성 구성모델을 비교적 간단한 수학적 합성유도방식에 기초하여 제안하였다. 이를 위하여 비등방성 modified Cam-Clay model을 일반응력공간으로 확장시켰으며generalized viscous theory를 단순화하여 각각 소성 및 점성의 구성관계로 활용하였다. Damage 원리를 구성모델에 추가하였으며, 모든 식의 변형 및 개발은 모델정수의 수를 감소시키는 원칙에 입각하여 수행하였다. 개발된 구성모델을 활용하여 점성토의 크리프거동을 예측하였으며 이를 실험결과와 비교분석하였다. 예측된 결과는 크리프파괴의 경우를 포함한 실험결과와 비교적 양호하게 일치하는 결과를 보여주었다.

Abstract ▼ AI-Helper

An elastic-plastic-viscous constitutive model was proposed based on a simple formulation scheme. The anisotropic modified Cam-Clay model was extended for the general stress space for the plastic simulation. The generalized viscous theory was simplified and used for the viscous constitutive part. A damage law was incoporated into the proposed constitutive model. The mathematical formulation and development of the model were performed from the point of view that fewer parameters be better employed. The creep behaviors with or without creep rupture were predicted using the developed model for cohesive soils. The model predictions were favorably compared with the experimental results including the undrained creep rupture, which is an important observed phenomenon for cohesive soils. Despite the simplicity of the constitutive model, it performs well as long as the time to failure ratio of the creep rupture tests is within the same order of magnitude.

주제어

AI 본문요약
AI-Helper

* AI 자동 식별 결과로 적합하지 않은 문장이 있을 수 있으니, 이용에 유의하시기 바랍니다.

가설 설정

The concept and the simplification, made in this research, of the generalized viscous theory (Perzyna, 1966) are briefly described in this section. The basic assumption of the theory is that the total strain rate can be resolved into time-independent elastic and plastic, and time-dependent plastic parts, which is called viscoplastic strain rate. The viscoplastic strain rate tensor e-f is given by:

제안 방법

It is clear that the introduction of initial damage makes it possible to simulate the results of creep rupture tests under high stress level, using the same damage parameters for all the tests. This, however, works well as long as the time to failure for different tests is within the same order of magnitude.
It is important to point out that it might have been possibe to use the isotropic modified Cam-Clay model instead of its anisotropic version used in this research. The prediction would not have been as good as it appears in Figs.
The load increments were applied at approximately 8 hour interval, and each increment was less than 10% of the undrained shear strength. Once the proper consolidation stress was reached, a prescribed deviatoric stresses (0.53, 0.55, 0.57, 0.60 kg/cm²) were applied and the creep tests initiated.
Regarding the viscous constitutive modeling, the respective consideration of the initial yield surface and the dynamic loading surface might be another development. The contribution of the anisotropic modified Cam-Clay model could be appreciated in that the normally consolidated specimen, on which the model is principally based, was used for the test and the prediction.
The generalized viscous theory by Perzyna (1966) has the advantages that it has successfully simulated the time-dependent behavior of soils with few model parameters, and the mathematical form of the theory can be easily formulated with the classical elastic-plastic derivation. The generalized viscous theory was simplified, in this research, for effective viscous modeling and obvious mathematical formulation in an elastic-plastic-viscous combination scheme. A damage law has been incorporated into the constitutive relation based on Vyalov (1986).
The basic concept is as Eq, (7) and it is based on Da仓lias (1982). The revision and application of each model, made in this research, were performed so that each model may employ fewer parameters for the practically easy usage of the model and for the avoidance of the confusion with the complicated parameters. The superscripts e, p, vp denote elastic, time-independent plastic, and time-dependent viscoplastic parts, respectively.

이론/모형

The elastic strain rate is time-independent and obtained using the generalized Hooke's law. The time-independent plastic strain rate is represented by the associated flow rule of Eq.

성능/효과

The values of the input parameters were evaluated using the test results by Bonaparte (1981) and Boija (1984). The hypothetical instantaneous strength parameter ro was assumed to be equal to the undrained shear strength (1, 4 kg/cm²) obtained from the test results. It was reported that the two creep tests with deviatoric stress equal to 0.

참고문헌 (18)

AI-Shannrani, M. A. and Sture, S. (1994), 'Characterization of Time dependent Behavior of Anisotropic Cohesive Soils', Computer Methods and Advances in Geomechanics, Siriwardane and Zaman (eds.) pp.505-511
Aubry, D., Kodaissi, E. and Meimon, E., A. (1985), 'Viscoplastic Constitutive Equations for Clays including Damage Law', Proc. 5th Int. Conf. Numerical Methods in Geomechanics, Vol.1, pp.421-428
Bonaparte, R. (1981), A Time-dependent Constitutive Model for Cohesive Soils, Ph. D. Dissertation, Univ. of California at Berkeley
Borja, R. I. (1984), Finite Element Analysis of the Time-dependent Behavior of Soft Clays, Ph. D. Dissertation, Stanford Univ
Chiarelli, A. S., Shao, J. F., and Hoteit, N. (2003), 'Modeling of Elastoplastic Damage Behavior of a Claystone', Int. J. of Plasticity, Month. 1, pp.23-45
Dafalias, Y. G. (1982), 'Bounding Surface Elastoplasticity-Viscoplasticity for Particulate Cohesive Media', Proc. IUTAM Symposium on Deformation and Failure of Granular Materials, P. A. Vermeer and H. J. Luger (eds.), A. A. Balkema, Publishers, Rotterdam, pp.97-107
Dafalias, Y. F. (1987), An Anisotropic Critical State Clay Plasticity Model. Constitutive Laws for Engineering Materials: Theory and Applications, Elsevier Science Publishing Co. Inc., pp. 513-521
de Sciarra F. M. (1997), 'General Theory of Damage Elastoplastic Models', J. of Engineering Mechanics, Vol.123, No.10, pp. 1003-1011

상세보기
Jenson, R. P., Plesha M. E., Edil, T. B., Bosscher P. J., and Kahla, N. B. (2001), 'DEM Simulation of Particle Damage in Granular Media', Int. J. of Geomechanics, pp.21-39
Kachanov, L. M. (1967), The Theory of Creep : Part I., National Lending Library for Science and Technology, Boston
Matsui, T. and Abe, N.(1988), 'Verification of Elasto-viscoplastic Model of Normally Consolidated Clays in Undrained Creep', Pro. 6th Int. Conf. of Numerical Methods in Geomechanics, Vol.1, pp.453-459.
Murayama, S., Kurihara, N. and Sekiguch, H. (1970), On Creep Rupture of Normally Consolidated Clays, Annuals, Disaster Pre-vention Research Institute, Kyoto University, No. 13B, pp. 525-541
Perzyna, P. (1966), 'Fundamental Problems in Viscoplasticity', Advances in Applied Mechanics, Vol.9, pp.243-377
Regel, V. R., Slutsker, A. I. and Tomashevsky, E. K. (1974), Kinetics Nature of Strength in Solid Bodies, Nauka, Moscow
Sekiguchi, H. (1984), 'Theory of Undrained Creep Rupture of Normally Consolidated Clay Based on Elasto- Viscoplasticity', Soils and Foundations, Vol.24, No.1, pp.129-147

상세보기
Singh, A. and Mitchell, J. K. (1968), 'General Stress-Strain-Time Function for Soils', J. of Soil Mechanics and Foundation, Vol. 94, No.SMI, pp.21-46
Vaid, Y. P. and Campanella, R. G. (1977), 'Time-dependent Behavior of Undrained Clay', J. of Geotechnical Engineering, No. GT 7, pp.693-709
Vyalov, S. S. (1986), Rheological Fundamentals of Soil Mechanics, Elsevier Science Publishing Company Inc., New York

내보내기 구분	파일저장 인쇄 메일전송
구성항목	기본정보 상세정보 관리번호, 논문명, 저널/프로시딩명, 저자 , 발행년, 권, 호, 시작페이지, 끝페이지, 발행기관 관리번호, 논문명, 대등논문명, 저자 , 저널/프로시딩명, 발행기관, 발행년, 발행언어, 권, 호, 시작페이지, 끝페이지, ISBN, ISSN, 주제분야, 키워드, 초록(한글), 초록(영문), 저자(소속기관)
저장형식	Text(ASCII format) Excel format RefWorks Direct Export RIS format (for Reference Manager, ProCite, EndNote), Scholar's Aids, Mendeley
메일정보	받는사람 (필수) @ 보내는사람 (선택) @ 제목 내용 KISTI 검색결과 이메일 서비스
안내	총 건의 자료가 검색되었습니다. 다운받으실 자료의 인덱스를 입력하세요. (1-10,000) 검색결과의 순서대로 최대 10,000건 까지 다운로드가 가능합니다. 데이타가 많을 경우 속도가 느려질 수 있습니다.(최대 2~3분 소요) 다운로드 파일은 UTF-8 형태로 저장됩니다. 파일의 내용이 제대로 보이지 않을실 때는 웹브라우저 상단의 보기 -> 인코딩 -> 자동선택 여부를 확인하십시오. ~ Text(ASCII format) Excel format

연합인증

점성토에 있어서의 크리프 거동 예측
Prediction of Creep Behavior for Cohesive Soils 원문보기

초록
AI-Helper

Abstract ▼ AI-Helper

주제어

AI 본문요약
AI-Helper

가설 설정

제안 방법

이론/모형

성능/효과

참고문헌 (18)

이 논문을 인용한 문헌

관련 콘텐츠

원문 보기

원문 URL 링크

이 논문과 함께 이용한 콘텐츠

AI-Helper ※ AI-Helper는 오픈소스 모델을 사용합니다.

선택된 텍스트

연합인증

점성토에 있어서의 크리프 거동 예측 Prediction of Creep Behavior for Cohesive Soils 원문보기

초록 용어보기논문에서 용어와 풀이말을 자동 추출한 결과로, 시범 서비스 중입니다. AI-Helper

Abstract ▼ AI-Helper

주제어

AI 본문요약 엑셀 다운로드 AI-Helper

가설 설정

제안 방법

이론/모형

성능/효과

참고문헌 (18)

이 논문을 인용한 문헌

관련 콘텐츠

원문 보기

원문 URL 링크

이 논문과 함께 이용한 콘텐츠

AI-Helper ※ AI-Helper는 오픈소스 모델을 사용합니다.

선택된 텍스트

점성토에 있어서의 크리프 거동 예측
Prediction of Creep Behavior for Cohesive Soils 원문보기

초록
AI-Helper

AI 본문요약
AI-Helper