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Effect of Electro-Osmosis Method on Marine Clay with Preloading

선행하중이 작용하는 해성점토지반에 전기삼투공법의 효과

  • Kang, Hongsig (School of Civil Engineering, Chungbuk National University) ;
  • Ahn, Kwangkuk (School of Civil Engineering, Chungbuk National University)
  • Received : 2014.11.19
  • Accepted : 2015.01.23
  • Published : 2015.02.01

Abstract

The Pre-loading method has been widely used for the soft ground stabilization but long construction times and the transport of large quantities of fill material are required. To shorten the construction periods, the vertical drain method is generally applied simultaneously. But the high costs of the fill materials along with environmental damages remain as the main difficulties to apply this method. Therefore, a complimentary way to reduce both the height of the embankment and the consolidation time is needed. In this study, the electro-osmosis method, which is able to shorten the consolidation time and minimize the damage of the environment, was performed with a model test. The results show that as the voltage increases the consolidation settlements, consolidation drainage and shear strength also increase while the water content decreases.

우리나라는 삼면이 바다로 둘러싸인 지리적 특성에 의해 연안 하부에 점토로 구성된 연약지반이 두껍게 형성되어 있다. 이러한 연약지반에 대규모 토목공사를 수행하기 위해선 연약지반 안정화 처리가 불가피하다. 연약지반 안정화 처리를 위해 일반적으로 선행하중공법이 널리 사용되고 있다. 선행하중공법은 공사기간이 길고 재하용 성토재료를 확보해야 한다는 단점을 가지고 있다. 공사기간을 단축시키기 위해 연직배수공법을 병용하여 사용하고 있다. 하지만 성토재료는 고비용 및 환경파괴를 발생시키기 때문에 성토체의 높이를 줄이면서 압밀시간을 단축시킬 수 있는 보완적인 방법이 필요하다. 따라서 본 연구에서는 이러한 단점을 보완하기 위해 압밀시간을 단축시키고 환경파괴를 최소화할 수 있는 전기삼투공법을 적용시킨 모형실험을 수행하였다. 그 결과 전압이 증가함에 따라 압밀침하량 및 압밀배수량, 전단강도는 증가하는 것으로 나타났으며, 함수비는 감소하는 것으로 나타났다.

Keywords

References

  1. Ahn, S. R. (2011), Effect of electrode efficiency for electroosmosis ground improvement, Master's thesis, Chungbuk National University. pp. 54-55 (in Korean).
  2. Aldrich, H. P. (1965), Precompression for support of shallow foundations, Journal of Soil Mechanics and Foundations Div., ASCE, Vol. 91, SM2, pp. 5-20.
  3. Asaoka, A. (1978), Obsernation precedure of settlement prediction, Soils and Foundations, JSSMGE, Vol. 18, No. 4, pp. 87-101. https://doi.org/10.3208/sandf1972.18.4_87
  4. Bang, J. H., Kim, W. H. and Han, I. Y. (1996), A study of field application on electro-osmotic consolidation for soft ground improvement, KGS 96, pp. 135-140 (in Korean).
  5. Casagrande, L. (1952), Electroosmotic stabilization, Journal of Boston Society of Civil Engineers, Vol. 39, pp. 51-83.
  6. Choi, Y. M. (2008), Prediction of consolidation settlements and strength increase of soft soil by pre-loading methods, Master's thesis, Yonsei University. pp. 59-60 (in Korean).
  7. Helmholtsz, H. (1879), Wiedemann's Annalen D. Physik, Vol. 243, Issue 7, pp. 337-382.
  8. Jeong, K. S. (2009), Characteristics on electrokinetic ground improvement using nano-geosynthetics, master's thesis, Chungbuk National University. pp. 65-66 (in Korean).
  9. Johnson, S. J. (1970), Precompression for improving foundation soils, Journal of the Soil Mech. and Foundations Div., ASCE, Vol. 96, pp. 111-144.
  10. Kim, G. H. (2012), A study on the consolidation behavior of soft grounds due to the embankment speed, Master's thesis, University of Seoul, pp. 54-55 (in Korean).
  11. Kim, S. S., Han, S. J. and Kim, J. Y. (2007), Estimation of shear strength of marine clay using electrokinetic cementation method, KSCE Journal of Civil Engineering, Vol. 27, No. 5, pp. 321-329 (in Korean).
  12. Lee, S. W. and Lee, Y. N. (1998), Electrokinetic strenthening of soft marine clays in E/K cell, Journal of the Korean Geotechnical Society, Vol. 14, No. 4, pp. 77-89 (in Korean).
  13. Lo, K. Y., Ho, K. S. and Inculet, I. I. (1991a), Field test of electro-osmotic strengthening of soft sensitive clays, Canadian Geotechnical Journal, Vol. 28, pp. 74-83. https://doi.org/10.1139/t91-008
  14. Lo, K. Y., Inculet, I. I. and Ho, K. S. (1991b), Electro-osmotic strengthening of soft sensitive clays, Canadian Geotechnical Journal, Vol. 28, pp. 66-73.
  15. Mitchell, J. K. (1991), Conduction phenomena from theory to geotechnical practice, Geotechnique, Vol. 41, pp. 299-340. https://doi.org/10.1680/geot.1991.41.3.299
  16. Shin, D. C. (2010), Charcteristics on electrokinetic ground improvement according to electrode types, Master's thesis, Chungbuk National University. pp. 46-47 (in Korean).