Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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Prediction of the Elastic Modulus of Improved Soil Using the Flat TDR System

판형 TDR 시스템을 이용한 개량지반의 탄성계수 예측

  • Song, Minwoo (Department of Civil Engineering, Chosun Univ.) ;
  • Kim, Wanmin (Department of Civil Engineering, Chosun Univ.) ;
  • Kim, Daehyeon (Department of Civil Engineering, Chosun Univ.) ;
  • Choi, Chanyong (High Speed Railway Research Division, Korea Railroad Research Institute)
  • Received : 2016.06.29
  • Accepted : 2016.09.22
  • Published : 2016.09.30
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Abstract

This study was conducted to solve the problem such as damage of completed compaction ground using the conventional compaction control method. In this study, a TDR system equipped with a flat type probe has been developed. Also, the Piezoelectric stack, which is an instrument for measuring the elastic wave on the ground, has been added to the developed flat type probe. In this study, the strength variation of reinforced soil with time was determined by using the TDR system. The value of compression and shear modulus increased from 198.65MPa to 541.80MPa and from 125.55MPa to 302.02MPa with time, respectively. Based on the test results, it has been confirmed that the developed TDR system can be used as reinforced effect analysis of soil and compaction control.

본 연구는 기존의 다짐관리 방법에서 다짐이 완료된 지반의 일부를 손상시켜야 하는 단점을 해결하기 위하여 진행되었다. 본 연구를 통하여 판형 Probe를 제작하였고, 제작한 Probe에 탄성파 측정 장치인 Piezoelectric stack을 결합하였다. 개발한 TDR 시스템을 이용하여 시간에 따른 개량토의 강도 변화를 측정하였다. 실험 결과, 압축탄성계수 및 전단탄성계수는 각각 78.92MPa에서 587.09MPa, 31.53MPa에서 182.44MPa로 증가함을 확인할 수 있었다. 실험 결과를 통하여 개발한 TDR 시스템을 이용하여 현장에서 개량지반의 시간경과에 따라 지반개량효과 및 다짐관리에 유용하게 활용할 것으로 기대된다.

Keywords

References

  1. Bolt, B. A., (1976), Nuclear Explosions and Earthquakes, W.H. Freeman and Company.
  2. Chan, C. M. (2010). "Bender element test in soil specimens: identifying the shear wave arrival time", EJGE, Vol.15, No.2010, pp.1263-1276.
  3. Chen, R., Drnevich, V. P., Yu, X., Nowack, R. L., and Chen, Y. (2007), "Time domain reflectometry surface reflections for dielectric constant in highly conductive soils", Journal of Geotechnical and Geoenvironmental Engineering, Vol.133, No.12, pp.1597-1608. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:12(1597)
  4. Choi, C. Y., Song, M. W., Kim, D. H., and Yu, X., (2016), "A New Non-Destructive TDR system Combined with a Piezoelectric Stack for Measuring Properties of Geomaterials", Materials, Vol.9, No.6, pp.439. https://doi.org/10.3390/ma9060439
  5. Drnevich, V., Lin, C., Yi, O., and Lovell, J. (2001a), "Real-time determination of soil type, water content, and density using electromagnetics", Joint Transportation Research Program, pp.177.
  6. Drnevich, V. P., Ashmawy, A. K., Yu, X., and Sallam, A. M. (2005), "Time domain reflectometry for water content and density of soils: study of soil-dependent calibration constants", Canadian Geotechnical Journal, Vol.42, No.4, pp.1053-1065. https://doi.org/10.1139/t05-047
  7. Feng, W., Lin, C. P., Deschamps, R. J., and Drnevich, V. P. (1999), "Theoretical model of a multisection time domain reflectometry measurement system", Water Resources Research, Vol.35, No.8, pp.2321-2331. https://doi.org/10.1029/1999WR900123
  8. Giese, K., and Tiemann, R. (1975), "Determination of the Complex Permittivity from Thin- Sample Time Domain Reflectometry: Improved Analysis of the Step Response Wave form" Advances in Molecular Relaxation and Interaction Processes, Vol.7, No.1, pp.45-59. https://doi.org/10.1016/0001-8716(75)80013-7
  9. Jung, S., Drnevich, V., and Abou Najm, M. (2013), "New Methodology for Density and Water Content by Time Domain Reflectometry", Journal of Geotechnical and Geoenvironmental Engineering, Vol.139, No.5, pp.659-670. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000783
  10. Kim, D. S., and Yoo, J. H. (2014). Field Water Content and Dry Density Measurement Using Time Domain Reflectometry. Journal of Korean Society of Hazard Mitigation, Vol.14, No.5, pp.101-108. https://doi.org/10.9798/KOSHAM.2014.14.5.101
  11. Lin, C. P. (1999), Time Domain Reflectometry for Soil Properties, Purdue University, Ph. D. Thesis.
  12. Molina, V., (2006), Measurement of Vp and Vs in dry, unsaturated and saturated sand specimens with piezoelectric transducers, University of Texas, Ph. D. Thesis.
  13. Park, C. S., Mok, Y. J., Choi, C. Y., and Lee, T. H. (2009). A Methodology for Quality Control of Railroad Trackbed Fills Using Compressional Wave Velocities: I. Preliminary Investigation. Journal of the Korean Geotechnical Society, Vol. 25, No.9, pp.45-55.
  14. Siddiqui, S.I. (1995), A New Method of Measuring Density and Moisture Content of Soil Using the Technique of Time Domain Reflectometry, Purdue University, Ph. D. Thesis.
  15. Siddiqui, S. I., Drnevich, V. P., and Deschamps, R. J. (2000), "Time Domain Reflectometry development for use in geotechnical engineering", Geotechnical Testing Journal, Vol.23, No.1, pp.9-20. https://doi.org/10.1520/GTJ11119J
  16. Song, M., Kim, D., and Choi, C. (2015). A New Calibration Equation for Predicting Water Contents With TDR. Journal of the Korean Geosynthetic Society, Vol.14, No.1, pp.59-65. https://doi.org/10.12814/jkgss.2015.14.1.059
  17. Song, M., Choi, C., and Kim, D. (2016). Development of a Flat-type TDR System for Compaction Control. Journal of the Korean Geotechnical Society, Vol.32, No.4, pp.51-61. https://doi.org/10.7843/KGS.2016.32.4.51
  18. Yu, X., and Drnevich, V.P. (2004), "Soil water content and dry density by time domain reflectometry", Journal of Geotechnical and Geoenvironmental Engineering, Vol.130, No.9, pp.922-934. https://doi.org/10.1061/(ASCE)1090-0241(2004)130:9(922)
  19. Yu, Xinbao, and Yu, Xiong, (2006), "Time Domain Reflectometry Tests of Multilayered Soils", Proc. TDR, Purdue University, pp. 1-16.
  20. Zambrano, C. E., Drnevich, V. P., and Yu, Xiong, (2006), "Soil Texture Characterization from TDR Waveform Analysis", Proc. TDR, Purdue University, pp.1-21.

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