Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
권호 표지
DOI QR코드

DOI QR Code

Experimental Study for Overtopping Discharges of Sea Dike having Low Mound and High Wave Wall (LMHW)

낮은 마운드 높이에 높은 상치구조물을 갖는 경사식 호안(LMHW 호안)의 월파량에 대한 실험적 연구

  • Jung, Jae-Sang (Rural Research Institute, Korea Rural Community Corporation) ;
  • Yoon, Jae-Seon (Rural Research Institute, Korea Rural Community Corporation)
  • 정재상 (한국농어촌공사 농어촌연구원) ;
  • 윤재선 (한국농어촌공사 농어촌연구원)
  • Received : 2019.10.14
  • Accepted : 2019.11.16
  • Published : 2019.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Overtopping discharge for sea dike having low mound and high wave wall (LMHW sea dike) is investigated with hydraulic experiments in this study. Vertical, Flare and Bullnose type wave walls are selected and Tetrapods (double layer) and Accropode (one layer) are adopted for armour layers of the front slope. The results of the hydraulic experiments are compared to the overtopping formulas for armoured rubble slopes and vertical sea dikes suggested by EurOtop Manual. Predicted overtopping discharges are underestimated as the roughness efficiency factors (γf) of armour blocks suggested by EurOtop are adopted when the overtopping formula for armoured rubble slopes sea dike is used. Meanwhile the predicted overtopping discharges agree well with the hydraulic experiments when the modified roughness efficiency factors redefined by multiplying efficiency factor of the heights of armoured crest berm and wave wall (γAR) are adopted. Return wall effects on a vertical wall (Kortenhaus et al., 2003; Pearson et al., 2004a) and the effects on a smooth dike slope (Van Doorslaer et al., 2015) in EurOtop Manual are investigated for Flare and Bullnose type wave walls. As a results of the comparison between experimental results and 2 formulas, return wall effect on a smooth dike was more valid for LMHW sea dike.

본 연구에서는 수리모형실험을 통해 낮은 마운드 높이에 높은 상치구조물을 갖는 경사식 호안(LMHW 호안)의 월파량에 관해 검토하였다. 상치구조물의 형식은 직립식, Flare 식 및 Bullnose 식을 적용하였으며, 호안 전면사면의 소파공은 테트라포드(2층적)와 아크로포드(1층적)를 적용하였다. 수리모형실험 결과는 EurOtop에서 제시하는 경사식 및 직립식 호안의 월파량 산정식과 비교하였다. LMHW 호안에 대해 경사식 호안의 월파량 산정식을 적용할 때 전면 소파공에 따른 조도영향계수(γf)로 EurOtop Manual에서 제시하는 계수를 적용할 경우 월파량이 과소평가 되었으나, 상치구조물 대비 마루높이 영향계수(γAR)를 곱한 수정조도계수를 적용한 경우에는 실험결과와 비교적 일치하였다. Flare 및 Bullnose 상치의 효과를 검토하기 위해 EurOtop Manual에서 제시하는 직립구조물 상부에 설치된 반파공의 효과(Kortenhaus et al., 2003; Pearson et al., 2004a)와 매끄러운 사면에 설치된 반파공의 효과(Van Doorslaer et al., 2015)를 적용하였다. 검토 결과 매끄러운 사면에 설치된 반파공의 효과가 낮은 마운드 높이에 높은 상치구조물을 갖는 경사식 호안에 보다 타당한 결과를 보였다.

Keywords

References

  1. Bretschneider, C.L. (1968). Significant waves and wave spectrum. Ocean Industry, Feb, 40-46.
  2. Bruce, T., van der Meer, J.W., Franco, L. and Pearson, J.M. (2006). A comparison of overtopping performance of different rubble mound breakwater armour. Proc. 30th Int. Conf. on Coastal Engineering, 5, 4567-4579.
  3. Bruce, T., van der Meer, J.W., Franco, L. and Pearson, J.M. (2009). Overtopping performance of different armour units for rubble mound breakwaters. Coastal Engineering, 56(2), 166-179. https://doi.org/10.1016/j.coastaleng.2008.03.015
  4. Coeveld, E.M., Van Gent, M.R.A. and Pozueta, B. (2005). Neural Network, Manual NN_Overtopping 2.0, CLASH: Workpackage 8, http://nn-overtopping.deltares.nl/.
  5. Hyundai Engineering and Construction (2005). Design report of construction of temporary sea dike for storage of dredging soil on southern container terminal of Busan new port (in Korean).
  6. Hyundai Development Company (2006). Design report of construction for extension of quay wall on Hwa-am wharf in Ulsan (in Korean).
  7. Kim, Y.-T., Lee, J.-I., Cho, Y.-S. and Ha, T.-M. (2010). Wave overtopping reduction coefficient of vertical wall for obliquely incident waves. Journal of Korean Society of Coastal and Ocean Engineers, 22(3), 149-155 (in Korean).
  8. Kim, Y.-T. and Lee J.-I. (2012). Wave overtopping formula for vertical structure including effects of wave period: Non-breaking conditions. Journal of Korean Society of Coastal and Ocean Engineers, 24(3), 228-234 (in Korean). https://doi.org/10.9765/KSCOE.2012.24.3.228
  9. Kortenhaus, A., Pearson, J., Bruce, T., Allsop, N.W.H. and van der Meer, J.W. (2003). Influence of parapets and recurves on wave overtopping and wave loading of complex vertical walls. Proc. Coastal Structures 2013, 369-381.
  10. Mase, H., Tamada, T., Yasuda, T., Hedges, T.S. and Reis, M.T. (2013). Wave runup and overtopping at seawalls built on land and in very shallow water. Journal of Waterway, Port, Coastal, and Ocean Engineering, ASCE, 139(5), 346-357. https://doi.org/10.1061/(ASCE)WW.1943-5460.0000199
  11. Mitsuyasu, H. (1970). On the growth of spectrum of wind-generated waves (2)-spectral shape of wind waves at finite fetch. Proc. Japanese Conf. Coastal Engineering, 1-7 (in Japanese).
  12. Molines, J. and Medina, J.R. (2015). Calibration of overtopping roughness factors for concrete armor units in non-breaking conditions using CLASH database. Coastal Engineering, 96, 62-70. https://doi.org/10.1016/j.coastaleng.2014.11.008
  13. Oh, S.-H. (2016). Analysis of the effect of reducing wave overtopping by wave return walls. Journal of Korean Society of Coastal and Ocean Engineers, 28(1), 1-6 (in Korean). https://doi.org/10.9765/KSCOE.2016.28.1.1
  14. Pearson, J., Bruce, T., Allsop, W., Kortenhaus, A. and van der Meer, J. (2004a). Effectiveness of recurve walls in reducing wave overtopping on sea walls and breakwaters. Proc. 29th Int. Conf. on Coastal Engineering, 4404-4416.
  15. Pearson, J., Bruce, T., Franco, L., van der Meer, J., Falzacappa, M. and Molino, R. (2004b). Report on additional tests, part B: Standard tests for roughness factors, CLASH SP4 report, University of Edinburgh, UK.
  16. Pullen, T., Allsop, N.W.H., Bruce, T., Kortenhaus, A., Schuttrumpf, H. and van der Meer, J.W. (2007). EurOtop. Wave overtopping of sea defences and related structures: Assessment Manual.
  17. Smolka, E., Zarranz, G. and Medina, J.R. (2009). Estudio experimental del rebase de un dique en talud de cubípodos. Libro de las X Journadas Espanolas de Costas y Puertos, Universidad de Cantabria-Adif Congresos, 803-809 (in Spanish).
  18. van der Meer, J.W., Allsop, N.W.H., De Rouck, J., Katenhaus, A., Pullen, T., Schüttrumpf, H., Troch, P. and Zanuttigh, B. (2016). EurOtop. Manual on wave overtopping of sea defences and related structures.
  19. van der Meer, J. and Bruce, T. (2014). New physical insights and design formulas on wave overtopping at sloping and vertical structures. Journal of Waterway, Port and Ocean Engineering, 140(6), doi: https://doi.org/10.1061/(ASCE)WW.1943-5460.0000221.
  20. Van Doorslaer, K., De Rouck, J., Audenaert, S. and Duquet, V. (2015). Crest modifications to reduce wave overtopping of nonbreaking waves over a smooth dike slope. Coastal Engineering, 101, 69-88. https://doi.org/10.1016/j.coastaleng.2015.02.004