Browse > Article

Resilient Moduli of Sub-ballast and Subgrade Materials  

Park, Chul-Soo (경희대학교 토목공학과)
Choi, Chan-Yong (한국철도기술연구원, 궤도노반연구팀)
Choi, Choong-Lak ((주)평화엔지니어링, SOC 사업부)
Mok, Young-Jin (경희대학교 토목건축대학)
Publication Information
Journal of the Korean Society for Railway / v.11, no.1, 2008 , pp. 54-60 More about this Journal
Abstract
In the trackbed design using elastic multilayer model, the stress-dependent resilient modulus $(E_R)$ is an important input parameter, that is, reflects substructure performance under repeated traffic loading. However, the evaluation method for resilient modulus using repeated loading triaxial test is not fully developed for practical purpose, because of costly equipment and the significantly fluctuated values depending on the testing equipment and laboratory personnel. The this study, the paper will present an indirect method to estimate the resilient modulus using dynamic properties. The resilient modulus of crushed stone, which is the typical material of sub-ballast, was calculated with the measured dynamic properties and the range of stress level of the sub-ballast, and approximated with the power model combined with bulk and deviatoric stresses. The resilient modulus of coarse grained material decreases with increasing deviatoric stress at a confining pressure, and increases with increasing bulk stress. Sandy soil (SM classified from Unified Soil Classification System) of subgrade was also evaluated and best fitted with the power model of deviatoric stress only.
Keywords
Resilient Modulus; Dynamic Properties; Crosshole Tests; Resonant Column Tests; Sub-ballast; Subgrade;
Citations & Related Records
연도 인용수 순위
  • Reference
1 한국철도기술연구원(2000), "철도강화노반재료 및 지지력 강화방안에 관한 연구," 보고서, KRRI 연구 00-37
2 Hwang, S. K. (1997), "Dynamic Properties of Natural soils," Ph. D. Dissertation, The University of Texas at Austin
3 권기철(1998), "변형특성을 고려한 노상토 및 보조기층 재료의 대체 MR 시험법," 박사학위논문, 한국과학기술원
4 Seed, H. B., Wong, R. T., Idriss, I. M., and Tokimatsu, K. (1984), "Moduli and Damping Factors for Dynamic Analysis of Cohesionless Soils," Report No. EERC 84/14, Earthquake Engineering Research Center, Univ. of California, Berkeley, September
5 목영진,박철수,임정열,최충락(2007),"현장탄성파시험을 이용한 강화노반의 시간적 강성 변화," 한국철도학회 춘계학술대회 논문집
6 한국과학기술원(1999), "현장부설시험장 노반재료의 동적설계정수 평가," 보고서
7 권기철(2004), "국내 보조기층 재료의 변형특성을 고려한 전체 변형률 영역의 구성모델 개발," 한국도로학회 논문집, 제6권, 제3호, pp.65-77
8 Uzan, J. (1985), "Characterization of Granular Material," Transportation Research Record 1022, TRB, National Research Counsil, Washington, D. C., pp.52-59
9 Moossazadeh, J., and Witczak, M. W. (1981), "Prediction of Subgrade Moduli for Soil that Exhibits Nonlinear Behavior," Transportation Research Record 810, TRB, National Research Counsil, Washington, D. C., pp.9-17
10 Kim, D. S. and Stokoe, K. H., II (1992), "Characterization of Resilient Modulus of Compacted Subgrade Soils Using Resonant Column and Torsional Shear Tests," Transportation Research Record 1369, TRB, National Research Counsil, Washington, D. C., pp.83-91