Browse > Article
http://dx.doi.org/10.7843/kgs.2018.34.3.13

Effect of Wave-Induced Seepage on the Stability of the Rubble Mound Breakwater  

Hwang, Woong-Ki (Dept. of Civil Engrg., Korea Maritime and Ocean Univ.)
Kim, Tae-Hyung (Dept. of Civil Engrg., Korea Maritime and Ocean Univ.)
Kim, Do-Sam (Dept. of Civil Engrg., Korea Maritime and Ocean Univ.)
Oh, Myounghak (Coastal Disaster Prevention Research Center, Korea Institution of Ocean Science & Technology)
Park, Jun-Young (Dept. of Geotechnical Engrg., Hyein Engineering & Construction)
Publication Information
Journal of the Korean Geotechnical Society / v.34, no.3, 2018 , pp. 13-27 More about this Journal
Abstract
To study how stable the rubble mound breakwaters are, one can look to the research of wave induced seepage flow through the pores of the rubble mound. Seepage flow is generally generated by the difference between the water level around the breakwater during a typhoon. The existing stability analysis method of the rubble mound is the static analysis which simply considers the force equilibrium taking into account the horizontal force acting on the concrete block induced by a wave (calculated by Goda equation) and the vertical force induced by the weight inclusive of the concrete block, quarry run, filter, and armor layer above the slipping plane. However, this static method does not consider the wave-induced seepage flow in the rubble mound. Such seepage may decrease the stability of the rubble mound. The stability of a rubble mound breakwater under the action of seepage was studied based on the results of CFD software (OpenFOAM) and Limit Equilibrium Method (GeoStudio). The numerical analysis result showed that the seepage flow decreased the stability of the rubble mound breakwaters. The results of the numerical analyses also revealed the stability of the rubble mound was varied with time. Especially, the most critical state happened at the condition of overtopping the concrete block, acting strong uplift pressure raising along side and underneath the concrete block, and generating high pore pressure inside rubble mound due to seepage flow. Therefore, it may be necessary to conduct a dynamic analysis considering the effect of wave-induce seepage flow together with the static analysis.
Keywords
Rubble mound breakwater; Typhoon; Wave-induced seepage flow; OpenFOAM; Stability;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 Macdonald, I.F., El-Sayed, M.S., Mow, K., and Dullien, F.A.L. (1979), "Flow through Porous Media-the Ergun Equation Revisited", Ind. Eng. Chem. Fundam., Vol.18. No.3, pp.199-208. http://dx.doi.org/10.1021/i160071a001.   DOI
2 Higuera, P., Lara, J. L., and Losada, I. J. (2014), "Three-dimensional Interaction of Waves and Porous Coastal Structures using Open- FOAM. Part I: Formulation and Validation", Coastal Engineering, Vol.83, pp.243-258.   DOI
3 Higuera, P., Losada, I. J., and Lara, J. L. (2015), "Three-dimensional Numerical Wave Generation with Moving Boundaries", Coastal Engineering, Vol.101, pp.35-47.   DOI
4 Kissling, K., Springer, J., Jasak, H., Schutz, S., Urban, K., and Piesche, M. (2010), "A Coupled Pressure based Solution Algorithm based on the Volume-of-fluid Approach for Two or more Immiscible Fluids", European Conference on Computational, Fluid Dynamics, ECCOMAS CFD., pp.1-16.
5 van Gent, M.R.A. (1995), "Porous Flow through Rubble-mound Material", Journal of Waterway, Port, Coastal, and Ocean Engineering, ASCE, Vol.121, No.3, pp.176-181.   DOI
6 Jacobsen, N.G., Fuhrman, D.R., and Fredsoe, J. (2012), "A Wave Generation Toolbox for the Open-source CFD Library: Open-Foam", International Journal for Numerical Methods in Fluids, Vol.70, No.9, pp.1073-1088.   DOI
7 Lee, K.-H., Bae, J.-H., An, S.-W., Kim, D.-S., and Bae, K.-S. (2016), "Numerical Analysis on Wave Characteristics around Submerged Breakwater in Wave and Current Coexisting Field by OLAFOAM", Journal of Korean Society of Coastal and Ocean Engineers, Vol.28, No.6, pp.332-349.   DOI
8 Bishop, A.W. (1955), The Use of the Slip Circle in the Stability Analysis of Slopes, Geotechnique, Vol.5, pp.7-17.   DOI
9 Kobayashi, N. (1977), Wave Runup and Overtopping on Beaches and Coastal Sstructures, Center for Applied Research Ocean Engineering Laboratory, University of Delaware. Research Report No: CACR, pp.97-109.
10 Che, G., Zheng, L, Zhang, Y., Dong, S., Kasugai, Y., and Kawakami, T. (2013), "Stability Analysis of Breakwater under Seepage Flow using DDA", Proceedings of the ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering OMAE, June 9-14, Nantes, France, pp.1-10.
11 Tonkin, S., Yeh, H., Kato, F., and Sato, S. (2003), "Tsunami Scour around a Cylinder", J. Fluid Mech., Vol.496, pp.165-192. http:// dx.doi.org/10.1017/S0022112003006402.   DOI
12 Sassa, S., Takahashi, H., Morikawa, Y., Takano, D., and Maruyama, K. (2014), "Tsunami Overflow Seepage-coupled Centrifuge Experiment for the Mound Scour", Proc. 7th International Conference on Scour and Erosion, Perth, pp.651-656.
13 Ministry of Oceans and Fisheries (2014), Design standard of harbor and fishing port.
14 Takahashi, H., Sassa, S., Morikawa, Y., Takano, D., and Maruyama, K. (2014), "Stability of Caisson Type Breakwater Foundation under Tsunami-induced Seepage", Soils Found,. Vol.54, No.4, pp.789.805. http://dx.doi.org/10.1016/j.sandf.2014.07.002.   DOI
15 Qi, W.-G. and Gao, F.-P. (2014), "Physical Modeling of Local Scour Development around a Large Diameter Monopile in Combined Waves and Current", Coast. Eng. Vol.83, pp.72-81. http://dx.doi.org/10.1016/j.coastaleng.2013.10.007.   DOI
16 Sumer, B.M. and Fredsoe, J. (2002), The Mechanics of Scour in the Marine Environment, Advanced Series on Ocean Engineering 17. World Scientific (552p.).
17 Sassa, S., Takahashi, H., Morikawa, Y., and Takano, D. (2016), "Effect of Overflow and Seepage Coupling on Tsunami-induced Instability of Caisson Breakwaters", Coastal Engineering, Vol.117, pp.157-165.   DOI
18 Sassa, S. (2014), "Tsunami-seabed-structure Interaction from Geotechnical and Hydrodynamic Perspectives", Geotech. Eng. J. Vol.45, No.4, pp.102-107 (Special Issue on Offshore and Coastal Geotechnics).
19 Sumer, B.M. (2014), Liquefaction Around Marine Structures, Advanced Series on Ocean Engineering 39. World Scientific (472p.).
20 Lage, J.L. (1998), "The Fundamental Theory of Flow through Permeable Media from Darcy to Turbulence", In: Ingham, D.B., Pop, I. (Eds.), Transport Phenomena in Porous Media. Elsevier Science, Oxford, pp.1-30.