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Analysis of Bearing Capacity Change of Forest Roadbed by Opening Year

개설시기에 따른 임도 노반의 지지력 변화분석

  • Chen, Hyeong-Uk (Department of Ecology and Environment System, Kyungpook National University) ;
  • Kim, Dong-Hyeon (Department of Ecology and Environment System, Kyungpook National University) ;
  • Lee, Kwan-Hee (Forest Technology and Management Research Center, National Institute of Forest Science) ;
  • Kim, Dong-Geun (Department of Ecology and Environment System, Kyungpook National University)
  • 천형욱 (경북대학교 생태환경시스템학과) ;
  • 김동현 (경북대학교 생태환경시스템학과) ;
  • 이관희 (국립산림과학원 산림기술경영연구소) ;
  • 김동근 (경북대학교 생태환경시스템학과)
  • Received : 2018.12.19
  • Accepted : 2019.05.29
  • Published : 2019.09.30

Abstract

The purpose of this study was to provide basic data for maintenance and repair of the forest road surfaces using the light drop weight test (LDWT), density test, and grain size analysis at four sites in Yeongyang-gun Mt. (2011y, 2014y, 2016y, and 2017y). In terms of the density test results, the opening density in 2011 was the highest at $2.0694g/cm^3$, and the opening density in 2017 was the lowest at $1.7443g/cm^3$. The grain size analysis showed that the proportion of large aggregates was highest at the opening in 2017, and the proportion of large aggregates decreased with the delay of opening date. From the LDWT results, $E_{vd}$ (the dynamic deformation coefficient) of the 2011y forest road was $35.7MN/m^2$, 2014y was $30.5MN/m^2$, 2016y was $28.6MN/m^2$, and 2017y was $23.5MN/m^2$. The $E_{vd}$ value for the oldest forests opened with the 2011y forest road was the highest, the average $E_{vd}$ value of the center portion was $21.45MN/m^2$, the average $E_{vd}$ value of the wheel portion of the banking part was $31.31MN/m^2$, and the average $E_{vd}$ value of the wheel portion of the cut part was $36.71MN/m^2$.

본 연구는 임도 유지관리 및 보수를 위한 기초자료를 제공하기 위하여 경상북도 영양군 임도를 대상으로 동평판재하시험(light drop weight test), 들밀도 시험 및 입도분석을 이용하여 개설시기 및 횡단위치별(성토부 차륜부(T0), 노면 중앙부(C), 절토부 차륜부(T1))에 따른 임도노반 지지력 분석을 실시하였다. 들밀도 및 입도분석결과, 들밀도는 2011년 개설임도가 $2.0694g/cm^3$으로 가장 높은 값을 나타냈으며, 2017년 개설임도가 $1.7443g/cm^3$으로 가장 낮은 값을 나타내었다. 입도분석은 2017년 개설임도에서 큰 골재의 비율이 가장 높게 나타났으며, 시기가 늦어질수록 큰 골재의 비율이 줄어드는 경향을 나타냈다. 동평판재하시험결과, 2011년 개설임도 $E_{vd}$가 평균 $35.9MN/m^2$, 2014년은 평균 $31.1MN/m^2$, 2016년은 평균 $26.7MN/m^2$, 2017년은 평균 $23.7MN/m^2$로 2011년 개설임도가 가장 높은 $E_{vd}$를 나타냈다. 또한 성토 차륜부는 평균 $21.2MN/m^2$, 절토 차륜부는 평균 $36.71MN/m^2$ 그리고 중앙부는 평균 $29.8MN/m^2$로 절토 차륜부가 가장 높은 $E_{vd}$를 나타냈다.

Keywords

References

  1. Choi, C.Y., Kim, H.K. and Bae, J.H. 2008. LFWD deformation modulus changes which follows in compaction energy from tentative embankment section. Journal of the Korean Society for Railway 2008(6): 1823-1830.
  2. Choi, C.Y., Lee, S.H., Bae, J.H. and Park, D.H. 2011. Evaluation of correlation between strain modulus (Ev2) and deformation modulus (ELFWD) using cyclic plate loading test and LFWD. Journal of Korean Goesynthetics Society. 10(3): 33-41.
  3. Department of Transport, Tourism and Sport. 2014. Guidelines on the depth of overlay to be uesd on rural regional and local roads. pp. 16.
  4. Fairbrother, S. 2011. Estimating forest road aggregate strength by measuring fundamental aggregate properties in proceedings council for forest engineering, Quebec City. pp. 1-9.
  5. Hoffmann, O.J.-M., Guzina B.B. and Drescher, A. 2004. Stiffness estimates using portable deflectometers. Journal of the Transportation Research Board. 1869(1): 59-66. https://doi.org/10.3141/1869-07
  6. Horak, E., Maina, J.W., Guiamba D. and Hartman, A. 2008. Correlation study with the light weight deflectometer in south africa. http://hdl.handle.net/10204/2437 (2008. 7. 11).
  7. Hwang, J.S., Ji, B.Y., Kweon, H.G. and Lee, K.H. 2018b. A study on sub-base composition effect of forest road using geosynthetics for passage of large loffing trucks. Journal of Korea Society of Forest Science. 107(3): 287-293. https://doi.org/10.14578/JKFS.2018.107.3.287
  8. Hwang, J.S., Ji, B.Y., Lee, K.H., Kweon, H.G. and Kim, M.H. 2018a. Bearing capacity reinforcing effect of forest road surface by construction of sub-base using geosynthetics. Journal of Korea Society of Forest Science. 107(2): 166-173. https://doi.org/10.14578/JKFS.2018.107.2.166
  9. Kang, H.B., Kim, K.J., Park, S.K. and Kim, J.R. 2008. A study on the relation between dynamic deflection modulus and in-situ CBR using a portable FWD. Journal of the Korea Institute for Structural Maintenance and Inspection 12(2): 149-155.
  10. Korea Forest Research Institute. 2017. Study on system atic network and optimal structure of forest road for forest production infrastructure. pp. 39-55.
  11. Korea Forest Service. 2015. Manual on the management of forest road. pp. 117-154.
  12. Korea Forest Service. 2018. Statistical yearbook of forestry. pp. 248.
  13. Lee, K.H., Oh, S.W., Ko, C.U. and Kim. D.G. 2015. Preliminary analysis of stabilization of forest road surface using geosynthetics. Journal of the Korea Dociety of Environmental Restoration Technology. 18(6): 51-60.
  14. Livneh, M. and Goldberg, Y. 2001. Quality assessment during road formation and foundation construction: Use of falling-weight deflectometer and light drop weight. Journal of the Transportation Research Board. 1755(1): 69-77. https://doi.org/10.3141/1755-08
  15. Park, Y.B. and Chung, H.S. 2003. A comparison of static and dynamic deformation modulus by dynamic plate test. Journal of Korean Geotechnical Society. 19(5): 335-342.
  16. United States Department of Agriculture Forest Service. 2011. Road Reconstruction Handbook. FSH 7709, 56: 67-72.
  17. Youn, I.R. and Oh, S.W. 2013. Estimate of the bearing capacity on subbase and subgrade with dynamic plate bearing test. Journal of the Korean Geo-environmental Society 14(8): 53-60. https://doi.org/10.14481/jkges.2013.14.12.053
  18. Zorn Instruments. 2005. Operating manual for light drop weight tester ZFG 2000. Maschinenbauingenieur bernd Zorn, Stendal Germany.