Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
권호 표지
DOI QR코드

DOI QR Code

Experimental Study on Reinforcement Effect of Geosynthetics for Surplus Soil, an Unsuitable Fill Material

성토재료로 부적합한 현장 발생토의 토목섬유 보강효과에 관한 실험적 연구

  • Hong, Young-Suk (Department of Civil and Environmental Engineering, Pusan National Univ.) ;
  • Im, Jong-Chul (Department of Civil and Environmental Engineering, Pusan National Univ.) ;
  • Kang, Sang-Kyun (Department of Civil and Environmental Engineering, Pusan National Univ.) ;
  • Yoo, Jae-Won (Research Institute of Industrial Technology, Pusan National Univ.) ;
  • Kim, Chang-Young (Research Institute of Industrial Technology, Pusan National Univ.)
  • Received : 2018.01.10
  • Accepted : 2018.02.21
  • Published : 2018.03.30
Download PDF
⟨ Previous Next ⟩

Abstract

Surplus soil is commonly used at construction sites, because suitable fill material is not always immediately available and leads to additional costs. However, most surplus soils do not meet the requirement of suitable fill material to achieve the stability and strength of embankments. In this study, Proctor compaction tests and field compaction tests were performed by installing geosynthetics to resolve the problems caused by compacting unsuitable soils. Compaction energy and the number of geosynthetics were changed under the type A- and D- and type A Proctor compaction tests (KS F 2312), respectively. The field compaction testing using geosynthetics was performed on surplus soils of high water content. Optimum water content and maximum dry density of compacted soil decreased and increased by reinforcing geosynthetics, respectively. Compaction curves behaved with geosynthetics as the compaction curves behaved with higher compaction energy. Efficient compaction was possible because the compaction energy increased to 2.10 and 2.71 times the compaction energy required to achieve the same maximum dry density with one and two geosynthetic layer(s), respectively. Furthermore, field compaction tests verified that efficient compaction was possible because the dry density of unsuitable surplus soils of high water content was increased by reinforcing geosynthetics.

양호한 성토재료는 현장에서 즉시 입수가 곤란하고 재료의 확보를 위한 추가적인 비용이 발생하여 각 현장에서는 현장 발생토를 직접 사용하는 경우가 많지만, 현장 발생토는 대부분 성토재료의 기준에 적합하지 않기 때문에 성토체의 안정성이나 강성을 확보하는데 어려움이 있다. 본 연구에서는 성토재료로 부적합한 흙의 다짐시 발생하는 문제점들을 개선하기 위하여 토목섬유를 보강하여 실내다짐시험과 현장다짐실험을 하였다. 실내다짐시험(KS F 2312)의 A, D다짐시험과 A다짐시험에서 다짐에너지와 토목섬유의 보강 층수를 다르게 하였고, 현장다짐실험은 함수비가 높은 현장 발생토에 토목섬유를 보강하고 다짐을 실시하였다. 그 결과, 실내다짐시험에서는 토목섬유를 보강함으로써 최적함수비는 감소, 최대건조밀도 증가하여 다짐곡선은 다짐에너지를 증가시켜 다짐한 경우와 비슷한 거동을 하였고, 건조밀도와 다짐에너지의 관계로부터 다짐에너지는 토목섬유를 1열, 2열 보강하였을 때 각각 평균 2.10배, 평균 2.71배 증가하여 토목섬유를 보강하고 다짐하면 큰 다짐에너지로 다짐한 것과 같은 효과로 더 효율적인 다짐이 가능한 것으로 분석되었다. 그리고 현장다짐실험에서 토목섬유를 보강함으로써 건조밀도는 증가하는 것으로 분석되어 다짐시 토목섬유를 보강하여 다짐을 실시하면 함수비가 높고 성토재료로 부적합한 현장 발생토를 사용하더라도 효율적인 다짐이 가능한 것으로 입증되었다.

Keywords

References

  1. AASHTO T99 (2015). Standard Method of Test for Moisture-Density Relations of Soils Using a 2.5-kg (5.5-lb) Rammer and a 305-mm (12-in.) Drop, American Association of State Highway and Transportation Officials (AASHTO), Washington, DC.
  2. AASHTO T180 (2015). Standard Method of Test for Moisture-Density Relations of Soils Using a 4.54-kg (10-lb) Rammer and a 457-mm (18-in.) Drop, American Association of State Highway and Transportation Officials (AASHTO), Washington, DC.
  3. ASTM D698-07 (2007). Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12 400 $ft-lbf/ft^3$(600 $kN-m/m^3$)), ASTM International, West Conshohocken, PA.
  4. ASTM D1557-09 (2009). Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 $ft-lbf/ft^3$ (2,700 $kN-m/m^3$)), ASTM International, West Conshohocken, PA.
  5. Hwang, S. C. and Oh, B. H. (2005), "The Compaction Characteristics Analysis of Domestic River Sands", Journal of the Korean Society of Road Engineers, Vol.7, No.4, pp.31-39. (in Korean)
  6. Im, J. C. (2016). A guide for soil engineering, 4th Edition, POD of CIR, Seoul, South Korea, pp.286-287. (in Korean)
  7. KS F 2311 (2001). Test method for soil density by the sand replacement method, Korean Standards Association, Seoul, South Korea. (in Korean)
  8. KS F 2312 (2001). Test method for soil compaction using a rammer, Korean Standards Association, Seoul, South Korea. (in Korean)
  9. Lee, J. Y., Jeoung, J. H., Choi, C. H., Kim, J. Y. and Jin, H. W. (2015), "Analysis of Correlation among Various Compaction Evaluation Methods for Estimating of the Bearing Capacity on Subgrades", J. Korean Geosynthetics Society, Vol. 14, No. 4, pp.45-58. (in Korean)
  10. Ministry of Construction and Transportation (1996), Road Design Standard, Ministry of Construction and Transportation, Seoul, South Korea, p.80. (in Korean)
  11. Ministry of Land, Infrastructure and Transport (2016), Road construction Design Standard, Korean Road Traffic Association, Seoul, South Korea, pp.4-22. (in Korean)
  12. Park, Y. T. (2014). An experimental study on the changes of compaction curve by reinforcement of geotextiles, M.Sc.Thesis, Pusan National University, Busan, South Korea. (in Korean)