Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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Improvement Effect and Field Application of Dynamic Replacement Using Crushed Rock

암버력 매립층의 동치환공법 현장 적용성 및 개량효과에 관한 연구

  • Lee, In-Hwan (Department of Civil and Environmental Engineering, Incheon National University) ;
  • Lee, Chul-Hee (Department of Infrastructure Safety Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Shin, Eun Chul (Department of Civil and Environmental Engineering, Incheon National University)
  • Received : 2019.10.17
  • Accepted : 2019.11.07
  • Published : 2019.12.30
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Abstract

The purpose of this study is to examine the effect of soft ground improvement by dynamic replacement with utilizing crushed rock. In order to understand the ground improvement effect when applying dynamic replacement method with crushed rock, the laboratory test and field test were performed. The internal friction angle and apparent cohesion were derived through direct shear test. The dynamic replacement characteristics were identified by analyzing the weight, drop, and number of blows needed for dynamic replacement. Through the field plate bearing test and density test, the bearing capacity and settlement of the improved ground were measured, and the numerical analysis were conducted to analyze the behavior of the improved ground. In this study, it proposes modified soil experimental coefficient(CDR) to 0.3~0.5 in the dynamic replacement method with crushed rock. Also when applying the dynamic replacement method using crushed rock, the particle size range is less than 100 mm, D90 is less than 80 mm and D15 is more than 30 mm.

본 연구는 건설현장에서 발생하는 암버력을 재활용하여 연약지반 개량재료로 활용가능한 동치환공법의 적용성과 연약지반 개량효과를 고찰하는 것을 목적으로 하고 있다. 암버력 매립층에서 동치환공법 적용시 지반보강 효과를 파악하기 위하여 현장지반 조사를 통해 수집한 암버력과 현장시료를 바탕으로 실내실험 및 현장시험을 수행하였다. 암버력의 전단시험을 통해 내부마찰각과 겉보기 점착력을 도출하였으며, 현장시료의 적용성과 문제점을 확인하고 동치환공법 적용시 필요한 중추의 무게, 낙하고, 타격횟수 등을 분석하여 동치환 특성을 파악하였다. 현장 평판재하시험과 밀도시험을 통하여 개량된 지반의 지지력과 침하량을 계측하였으며, 수치해석을 통해 개량지반의 거동을 예측하였다. 본 연구를 통해서 암버력 매립층의 동치환공법시 지반 실험계수 CDR은 0.3~0.5로 수정 제안하였고, 100mm 이하 D90은 80mm이하, D15는 30mm이상의 입도범위를 가지는 암버력을 사용할 것을 제안하였다.

Keywords

References

  1. Choi, S. J. (2008), Reliability Analysis of Ground Improvement through the Dynamic Compaction on Silty Sand Ground, Master thesis, Seoul National University of Technology. (in Korean)
  2. Chow, Y. K., Yong, D. M., Yong, K. Y. and Lee, S. L. (1992), "Dynamic Compaction Analysis", Journal of Geotechnical Engineering, ASCE, Vol.118, No.8, pp.1141-1157. https://doi.org/10.1061/(ASCE)0733-9410(1992)118:8(1141)
  3. Chow, Y. K., Yong, D. M., Yong, K. Y. and Lee, S. L. (1994), "Dynamic Compaction of Loose Granular Soils : Effects of Print Spacing", Journal of Geotechnical Engineering, ASCE, Vol.120, No.7, pp.1115-1133. https://doi.org/10.1061/(ASCE)0733-9410(1994)120:7(1115)
  4. Duncan. J. M, Byrne. P., Wong. K. S. and Mabry. P. (1980), "Strength, Stress-Strain and Bulk Modulus Parameters for Finite Element Analyses of Stresses and Movements in Soil Masses", University of California at Berkeley, Report No. UCB/GT/80-01, pp.70.
  5. Federal Highway Administration. (1986), "Dynamic Compaction for Highway Construction", Vol.1, Design and Construction Guidelines. FHWA/RD 86-133.
  6. Federal Highway Administration. (1995), Dynamic Compaction, Geotechnical Engineering Circular No.1, pp.27-38.
  7. Gambin, M. P. (1979), "Menard Dynamic Consolidation", presented at ASCE Seminar on Ground Reinforcement, George Washington University, Washington, D.C.
  8. Kim, D. S., Kweon, G. C., Park, H. C. and Kim, S. I. (1996), 'Evaluation of Ground Densification Due to Dynamic Compaction Using SASW Method", Journal of the Korean Geotechnical Society, No.3, pp.227-236. (in Korean)
  9. Kim, H. S. (2011), A Study of Long-term Settlement Estimation of Dynamic Compacted High Rock Embankment, Master Thesis, Incheon National University. (in Korean)
  10. Kim, S. H. (2018), "Land Analysis of Effective Depth of Dynamic Replacement Method", Journal of the Society of Disaster Information, Vol.14, No.3, pp.305-314. (in Korean)
  11. KS F 2444 (2018), Standard Test Method for Plate Bearing Test on Shallow Foundation, Korea Standard Association.
  12. Lee, J. H. (2007), The Comparison Study of Soil-Filling Method for Extremely Soft Ground Based on Numerical Analysis, Master Thesis, Chonnam National University. (in Korean)
  13. Lee, J. H. (2017), A Case Study of Ground Improvement Containing Silt and Clay Layers by Dynamic Compaction, Master Thesis, Hanyang University. (in Korean)
  14. Mayne, P. W. and Jones, J. S. (1983), "Impact Stresses during Dynamic Compaction", Journal of the Geotechnical Engineering, ASCE, Vol.109, No.10, pp.1342-1347. https://doi.org/10.1061/(ASCE)0733-9410(1983)109:10(1342)
  15. Menard, L. (1975), "Discussion of Dynamic Compaction in Ground Treatment by Deep Compaction", A. Penman, edition, Institute of Civil Engineers, London, pp.956-96, 106-107.
  16. Na, Y. M. (1997), "Dynamic measurement during Dynamic Compaction", Journal of the Korean Geotechnical Society, No.3, pp.81-88. (in Korean)
  17. Pan, J. L. and Selby A. R. (2002), "Simulation of Dynamic Compaction of Loose Granular Soils", Advances in Engineering Software, Vol.33, pp.631-640. https://doi.org/10.1016/S0965-9978(02)00067-4
  18. Park, J. H. (2013), Improving Effect by Dynamic Compaction with Ground Condition, Master Thesis, Chungbuk National University. (in Korean)
  19. Qian, J. H. (1986), "Dynamic Consolidation from Practice to Theory", Proc 8th Asian Regional Conference on Soil Mechanics and Foundation Engineering, Vol.2, pp.213-217.
  20. Yoo, J. S. (2016), Analysis of Effective Depth and Improvement Effect of Dynamic Replacement Method in Silty Clays, Ph.D. Thesis, Incheon National University. (in Korean)