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Analysis of Application Cases and Evaluation of Effectiveness on Portable Dynamic Cone Penetration Test (DCPT) to Identify the Deterioration Cause of Damaged Reinforced Earth Walls

보강토옹벽의 피해원인 규명을 위한 휴대형 동적콘관입시험(DCPT) 적용사례 분석 및 효용성 평가

  • Lee, Kwang-Wu (Department of Infrastructure Safety Research, Korea Institute of Civil engineering and building Technology) ;
  • Cho, Sam-Deok (Department of Infrastructure Safety Research, Korea Institute of Civil engineering and building Technology)
  • Received : 2020.11.23
  • Accepted : 2020.12.24
  • Published : 2020.12.30

Abstract

In this study, a total of six site cases were reviewed to assess the site applicability of portable dynamic cone penetration test (DCPT) by identifying the cause of damage to the damaged reinforced earth wall using portable dynamic cone penetration test. An improved dynamic concrete penetration tester was used at the site to enable ground surveys of more than 6 meters. The test results were compared with the results of the standard penetration test (SPT) and the correlation was analyzed. Through the analysis of various field application cases, it was found that portable dynamic cone penetration test was very convenient to apply at the site of the damaged reinforced earth wall, and DCPT could play a major role in identifying the cause of damage and verifying stability of the retaining wall by continuously identifying the ground strength. In addition, it was found that the results of the dynamic cone penetration test and the standard penetration test showed a correlation of N≒(1/3~2/3)·Nd in sandy soil.

본 연구에서는 휴대형 동적콘관입시험(DCPT)을 활용하여 손상된 보강토옹벽의 피해원인을 규명하고 대책방안을 마련한 총 6곳의 현장사례를 검토하여 휴대형 동적콘관입시험의 현장 적용성을 평가하였다. 현장에서는 하부 로트의 결합 연장을 통하여 6m 이상의 지반조사가 가능하도록 개량된 동적콘관입시험기를 사용하였으며, 그 결과를 표준관입시험 결과와 비교하여 상관 관계를 분석하였다. 다양한 현장 적용사례 분석을 통하여, 휴대형 동적콘관입시험이 손상된 보강토옹벽 현장에서의 적용이 매우 편리하며, 연속적으로 개략적인 지반강성을 파악하여 옹벽의 피해원인을 규명하고 안정성을 확인하는데 큰 역할을 할 수 있음을 알 수 있었다. 또한, 동적콘관입시험 및 표준관입시험 결과를 비교, 분석해 본 결과, 사질토 지반에서는 N≒(1/3~2/3)·Nd 정도의 상관관계가 나타남을 알 수 있었다.

Keywords

Acknowledgement

This research was supported by the Korea Institute of Civil Engineering and Building Technology under Ministry of Science and ICT, Main Project "Commercialization Support and Development of Retaining Wall reflecting Stability/Landscape through LED applicable Multi-Block combination". (Project Number: 20200431-001)

References

  1. Ajayi, L. A. and Balogun, L. A. (1988), "Penetration testing in tropical lateritic and residual soils-Nigerian experience", Proc. of the International Symposium on Penetration Testing, ISOPT-1, Orlando, Vol.2, pp.315-328.
  2. Chang, M. F. (1988), "In situ testing of residual soils in Singapore", Proc. of 2nd International Conference on Geomechanics in Tropical Soils, Singapore, Vol.2, pp.97-108.
  3. Kim, B. I., Jeon, S. I. and Lee, M. S. (2006), "Comparison of field bearing capacity tests to evaluate the field application of dynamic cone penetrometer test", Journal of Korean Society of Road Engineers, Vol.8, No.4, pp.75-85.
  4. Kim, S. Y., Byun, Y. H., Hong, W. T., Kim, K. H. and Lee, J. S. (2014a), "Correlation between strength and dynamic cone penetration index", Proc. of 2014 Spring Conf. of the Korean Society for Railway, KSR2014S109.
  5. Kim, U. G., Zhuang, L. and Lee, K. W. (2014b), "Development of advanced dynamic cone penetrometer test apparatus and its application performance evaluation", Journal of Korean Geosynthetics Society, Vol.13, No.4, pp.119-131. https://doi.org/10.12814/jkgss.2014.13.4.119
  6. Luo X., Salgado R. and Altschaeffl A. G. (1998), "Dynamic cone penetration test to assess the mechanical properties of the subgrade soil", Purdue Univ., FHWA/IN/JTRP-98/13, Final report.
  7. Meigh, A. C. and Nixon, I. K. (1961), "Comparison of In Situ Tests for Granular Soils", Proc. of 5th Int. Conf. on Soil Mechanics and Foundation Engineering, Paris, Vol.1, pp. 499-507.
  8. Meyerhof, G. G. (1956), "Penetration tests and bearing capacity of cohesionless soils", Journal of the Soil Mechanics and Foundations Division, Vol.82, No.SM1, January, pp. 1-18.
  9. Oh, H. J., Lee, B. J., Lee, J. K. and Oh, S. U. (2009), "Relationship between the DCPT and the SPT", Korean Geo-Environmental Conference, pp.132-135.
  10. Scala, A. J. (1956), "Simple methods of flexible pavament design using cone penetrometers", Proc. of 2nd Australian-New Zealand Conf. on Soil Mechanics and Foundation Engineering.
  11. 木村 好延, 谷垣 勝久 (2012), "河川堤防における簡易動的 コーン貫入試験の実施例", 全地連 技術フォーラム2012 新潟, CD-ROM.
  12. 小林 豊, 谷内江 敬太, 石尾 政男, 小島 一宏, 森本 崇 (2012), "簡易動的コーン貫入試験の適用性について(その2)", 全地連 技術フォーラム2012 新潟, CD-ROM.
  13. 森本 崇, 松本 和正, 小島 一宏, 太田 佳之, 平松 良太 (2013), "簡易動的コーン貫入試験の適用性について(その3)", 全地連 技術フォーラム2013 新潟, CD-ROM.
  14. 高瀨 晶弘, 笹田 麻純 (2012), "地盤変形調査で簡易動的コーン貫入試験の適用", 全地連 技術フォーラム2012 新潟, CD-ROM.
  15. 谷内江 敬太, 松本 和正, 石尾 政男, 小林 豊, 宮西 広基, 森本崇 (2013), "簡易動的コーン貫入試験器の改良について", 全地連 技術フォーラム2013 長野, CD-ROM.