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Evaluation of Applicability of HWAW (Harmonic Wavelet Analysis of Waves) Method in Determining Grouting Effect in Dam and Embankment

제체 그라우팅 효과 평가를 위한 HWAW방법의 적용성 평가

  • Received : 2016.03.02
  • Accepted : 2016.05.01
  • Published : 2016.05.31

Abstract

Dam and embankment are very important civil structures. Grouting is widely used to repair and maintain dam and embankment, and it is important to evaluate the effect of grouting for dam safety. The non-destructive method based on determination of wave velocity in the dam or embankment is effectively used to evaluate grouting effect because wave velocity is identical with stiffness and grouting increases local stiffness in a dam. In this paper, HWAW (Harmonic wavelet analysis of waves) method was applied to evaluate the grouting effect. HWAW method can determine two-dimensional shear wave velocity map with good spatial resolution and the shear velocity profile by the proposed method is sensitive to a variation of stiffness of target system. Through numerical simulation and field tests, the applicability of HWAW method in determining grouting effect is shown.

댐 제방과 같은 제체는 매우 중요한 토목구조물로서 이러한 제체의 유지 보수에는 그라우팅 공법이 많이 사용된다. 그라우팅을 사용한 유지 보수를 통해 제체 안정성을 확보하기 위해서는 그라우팅 시공 결과의 건전성이 확보되어야 한다. 따라서 그라우팅을 사용한 유지 보수에 있어 그라우팅 결과의 건전성 평가는 매우 중요하다. 그라우팅 시공에 따른 제체의 전단파 속도 변화량은 그라우팅 시공 결과의 건전성 평가에 효과적으로 사용될 수 있다. 전단파 속도는 대상 매질의 강성을 나타내며, 그라우팅은 대상 매질의 강성을 변화 시키기 때문에 전단파 속도 변화량 측정을 통해 그라우팅 효과의 정성적인 평가가 가능하다. 이를 위해서는 시공 전 후 제체 단면의 공간에 따른 전단파 속도 분포를 결정할 수 가 있어야 한다. 본 연구에서는 HWAW(Harmonic Wavelet Analysis of Waves)방법을 전단파 속도 결정을 통한 그라우팅 시공 결과의 건전성 평가에 적용하였다. HWAW방법은 단순한 장비를 사용하여 대상 시스템의 강성변화에 민감하다. 또한 높은 공간 해상도를 가지는 전단파 속도 분포 결정이 가능한다. 제안된 방법의 타당성을 검토하고자 수치모의 실험과 현장 적용실험을 수행하였으며, 이를 통해 제안된 그라우팅 효과 평가 방법의 적용성을 확인할 수 있었다.

Keywords

References

  1. Joh, S.H. (1996), Advanced in interpretation and analysis techniques for spectral analysis of surface waves (SASW) measurements. PhD Dissertation, The Unversity of Texas at Austin.
  2. Kim, D.S., Bang, E.S., and Kim, W.C. (2004), "Evaluation of Various Down Hole Data Reduction Methods to Obtain Reliable VS Profile", Geotechnical Testing Journal, Vol.27, No.6, pp.585-597.
  3. Kim, D.S., Kim, J.T., Park, H.J., Bang, E.S., and Park, H.C. (2015), "Verification Study for Surface Wave Method bsed on Harmonic Wavelet Analysis Waves Using a Large-scale Model Test Site", J. of Applied Geophysics, 113, pp.74-85. https://doi.org/10.1016/j.jappgeo.2014.12.013
  4. Kausel, E. and Roesset, J.M. (1981), Stiffness matrices for layered soils, Bull Seismol Soc Am, 71, pp.1743-1761.
  5. Kausel, E. and Peek, R. (1982), Dynamic loads in the interior of a layered stratum: an explicit solution, Bull Seismol Soc Am, 72, pp.1459-1481.
  6. Park, C.B., Miller, R.D., and Xia, J. (1999), "Multi-channel Analysis of Surface Waves", Geophysics, Vol.64, No.3, pp.800-808. https://doi.org/10.1190/1.1444590
  7. Park, H.C. and Kim, D.S. (2001), Evaluation of the Dispersive Phase and Group Velocities using Harmonic Wavelet Transform, NDT&E International, Vol.34, No.7, pp.457-467. https://doi.org/10.1016/S0963-8695(00)00076-1
  8. Park, H.C. and Kim, D.S. (2004a), "Development of Seismic Characterization Method Using HWAW(Harmonic Wavelet Analysis of Wave) Method (I)", Journal of the Korean Society of Civil Engineers, Vol.24, No.2C, pp.105-115.
  9. Park, H.C. and Kim, D.S. (2004b), "Development of Seismic Characterization Method Using HWAW(Harmonic Wavelet Analysis of Wave) Method (II)", Journal of the Korean Society of Civil Engineers, Vol.24, No.2C, pp.117-124.
  10. Park, H.C., Kim, D.S., and Lee, B.S. (2004), "Field Application of New Seismic Site Characterization Using HWAW (Harmonic Wavelet Analysis of Waves) Method", Journal of the Korean Geotechnical Society, Vol.20, No.6, pp.1-9.
  11. Park, H.C., Kim, D.S., Bang, E.S., and Kim, J.T. (2007), Seismic Site Characterization using HWAW(Harmonic Wavelet Analysis of Waves) Method, 4th International Conference on Earthquake Geotechnical Engineering, Thessaloniki, Greece.
  12. Park, H.C. and Hwang, H.J. (2012), "Development of Automated Inversion Method for HWAW Method Using Genetic Algorithm", Journal of the Korean Geotechnical Society, Vol.28, No.8, pp.55-63.
  13. Park, H.C. (2012), HWAW (Harmonic Wavelet Analysis of waves) Analyzer v2.0 User's Manual, ChungNam National University.
  14. Song, S.H., Jang, W.W., Kim, J.H., Kim, J.S. and Kim, J.C. (2002), "Electrical Resistivity Survey for Evaluation of Reinforced Region by Cement Grouting in Dike", Engineering Geology, Vol.12, No.1, pp.63-73.
  15. Society for the research of civil enginnering construction method (2003), Practical Grouting Method, Construction Information Co.
  16. Stokoe, K. H. and Woods, R. D. (1972), "In Situ Shear Wave Velocity by Cross-hole Method, Journal of the Soil Mechanics and Foundations Divisions", ASCE, Vol.98, No.SM5, pp.443-459.
  17. Stokoe, K.H., Wright, S.G., Bay, J.A., and Roesset, J.M. (1994), Characterization of geotechnical sites by SASW method. In: Woods RD, editor. Geotechnical characterization of sites, New Delhi, India: Oxford and IBH Publishing Co., pp.15-26.