Wave Hydrodynamics across Steep Platform Reefs: A Laboratory Study

Dinh Quang Cuong, Thieu Quang Tuan

Abstract


This paper presents a laboratory study on wave transmission across steep platform reefs, aiming at furthering knowledge of wave hydrodynamics and establishing empirical formulations of spectral wave parameters across the reef flat. The ultimate aim of this study is to determine the design wave load to design fixed offshore structures on coral reefs flat. The process of wave transmission across the underground coral strip with a large front slope has been studied on a physical model in the wave trough with nearly 300 experimental cases combined from 05 underground band models and many random wave scenarios and scenarios at different submerged depths. Experimental results show that the abrupt transition in depth from deep water ahead to relatively shallow water in the reef is responsible for the difference in the wave at the top of the strip compared to the wave on the normal beach, especially regarding the statistical distribution of the wave height. Breaking waves at the abrupt transition have deviated the wave height distribution curve from the deep-water (Rayleigh) theoretical distributions and even the existing shallow-water distributions, including the effect of breaking waves. Two sets of empirical formulations of the spectral wave parameters (Hm0 and Tm-1, 0) are eventually derived for the surf zone and the region behind the surf zone, respectively. These local wave parameters can be used as inputs to a wave height distribution model for determining other design characteristic wave heights on steep platform reefs.

 

Doi: 10.28991/CEJ-2022-08-08-015

Full Text: PDF


Keywords


Wave Transmission; Platform Reefs; Reef Flat; Large Front Slope; Wave Breaking.

References


Nelson, R. C. (1994). Depth limited design wave heights in very flat regions. Coastal Engineering, 23(1–2), 43–59. doi:10.1016/0378-3839(94)90014-0.

Gourlay, M. R. (1994). Wave transformation on a coral reef. Coastal Engineering, 23(1–2), 17–42. doi:10.1016/0378-3839(94)90013-2.

Yao, Y., Huang, Z., Monismith, S. G., & Lo, E. Y. M. (2013). Characteristics of monochromatic waves breaking over fringing reefs. Journal of Coastal Research, 29(1), 94–104. doi:10.2112/JCOASTRES-D-12-00021.1.

Battjes, J. A. (1974). SURF SIMILARITY. Coastal Engineering Proceedings, 1(14), 26. doi:10.9753/icce.v14.26.

Nakaza, E., & Hino, M. (1991). Bore-like surf beat in a reef zone caused by wave groups of incident short period waves. Fluid Dynamics Research, 7(2), 89–100. doi:10.1016/0169-5983(91)90062-N.

Lowe, R. J., Falter, J. L., Bandet, M. D., Pawlak, G., Atkinson, M. J., Monismith, S. G., & Koseff, J. R. (2005). Spectral wave dissipation over a barrier reef. Journal of Geophysical Research: Oceans, 110(4), 1–16. doi:10.1029/2004JC002711.

Demirbilek, Z., Nwogu, O. G., & Ward, D. L. (2007). Laboratory study of wind effect on runup over fringing reefs, Report 1: data report. Technical report, Coastal and Hydraulics Laboratory, Engineering Research and Development Center, Vicksburg, United States.

Buckley, M. L., Lowe, R. J., Hansen, J. E., & Van Dongeren, A. R. (2015). Dynamics of wave setup over a steeply sloping fringing reef. Journal of Physical Oceanography, 45(12), 3005–3023. doi:10.1175/JPO-D-15-0067.1.

Becker, J. M., Merrifield, M. A., & Yoon, H. (2016). Infragravity waves on fringing reefs in the tropical Pacific: Dynamic setup. Journal of Geophysical Research: Oceans, 121(5), 3010–3028. doi:10.1002/2015JC011516.

Buckley, M. L., Lowe, R. J., Hansen, J. E., Van Dongeren, A. R., & Storlazzi, C.D. (2018). Mechanisms of wave-driven water level variability on reef-fringed coastlines. Journal of Geophysical Research: Oceans, 123(5), 3811–3831. doi:10.1029/2018JC013933.

Tuan, T. Q., & Cuong, D. Q. (2019). Distribution of wave heights on steep submerged reefs. Ocean Engineering, 189, 106409. doi:10.1016/j.oceaneng.2019.106409.

van der Meer, J. W., Briganti, R., Zanuttigh, B., & Wang, B. (2005). Wave transmission and reflection at low-crested structures: Design formulae, oblique wave attack and spectral change. Coastal Engineering, 52(10–11), 915–929. doi:10.1016/j.coastaleng.2005.09.005.

Miche, M. (1954). Undulatory Movements of the Sea in Constant or Decreasing Depth: Limited Form of the Wave at the Time of Breaking Application to Marine Structures. College of Engineering, University of California, California, United States.

Hofland, B., Chen, X., Altomare, C., & Oosterlo, P. (2017). Prediction formula for the spectral wave period Tm-1,0 on mildly sloping shallow foreshores. Coastal Engineering, 123, 21–28. doi:10.1016/j.coastaleng.2017.02.005.

Dalrymple, R. A., Kirby, J. T., & Hwang, P. A. (1984). Wave Diffraction Due to Areas of Energy Dissipation. Journal of Waterway, Port, Coastal, and Ocean Engineering, 110(1), 67–79. doi:10.1061/(asce)0733-950x(1984)110:1(67).


Full Text: PDF

DOI: 10.28991/CEJ-2022-08-08-015

Refbacks

  • There are currently no refbacks.




Copyright (c) 2022 Quang Cuong DINH, Quang Cuong DINH, Quang Tuan THIEU

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
x
Message