The Influence of Crest Width and Working States on Wave Transmission of Pile–Rock Breakwaters in the Coastal Mekong Delta
Abstract
:1. Introduction
2. Laboratory Experiments
2.1. Experiment Equipment Setup
2.2. Installation of Equipment and Model Setup
2.3. Experimental Scenarios
2.3.1. Wave Conditions
2.3.2. Experimental Structures
2.3.3. Testing Scenarios
- One test without PRBW and three tests with three crest widths (B24, B38, and B52);
- Seven tests with a changing water level and crest freeboard (Rc);
- Tests changing ten parameters of the waves (Hs, Tp, and L).
3. Results and Discussion
3.1. Wave Spectrum Validation
3.2. Experimental Analysis
3.2.1. The Effect of Crest Width on the Wave Transmission Coefficient
3.2.2. The Effect of Crest Width on the Wave Reflection Coefficient
3.2.3. The Effect of Crest Width on Energy Dissipation
3.3. Development of Experimental Equations for the Wave Transmission Coefficient
3.4. Comparison of Different Empirical Formulas for Pile–Rock Breakwaters
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Dimension | Scenarios | Actual (cm) | Model (cm) |
---|---|---|---|
Height | - | 280 | 40 |
Length | - | 850 | 120 |
Width (B) | B24 | 170 | 24 |
B38 | 270 | 38 | |
B52 | 370 | 52 | |
Rock mix | - | 30–50 | 4–7 |
Centrifugal pile diameter | - | 30 | 4 |
Scenarios | Water Depth D (cm) and Crest Freeboard Rc (cm) | Wave Parameters |
---|---|---|
No PRBW B24 B38 B52 | D = 20 cm (Rc = +20 cm) D = 25 cm (Rc = +15 cm) D = 30 cm (Rc = +10 cm) D = 35 cm (Rc = +5.0 cm) D = 40 cm (Rc = +0.0 cm) D = 45 cm (Rc = −5.0 cm) D = 50 cm (Rc = −10 cm) | Hs = 12 cm; Tp = 1.51 s Hs = 12 cm; Tp = 1.89 s Hs = 12 cm; Tp = 2.27 s Hs = 12 cm; Tp = 2.65 s Hs = 17 cm; Tp = 1.89 s Hs = 17 cm; Tp = 2.27 s Hs = 17 cm; Tp = 2.65 s Hs = 22 cm; Tp = 2.27 s Hs = 22 cm; Tp = 2.65 s Hs = 27 cm; Tp = 2.65 s |
Empirical Equations | R2 | MSE | RMSE |
---|---|---|---|
van der Meer et al. (2005) | 0.88 | 0.0028 | 0.053 |
d.Angremond et al. (1996) | 0.78 | 0.0041 | 0.064 |
Linear equation (current study) | 0.82 | 0.0033 | 0.058 |
Non-linear equation (current study) | 0.73 | 0.0044 | 0.066 |
Tuan et al. (2018) | 0.04 | 0.0224 | 0.150 |
Tuan and Luan. (2020) | 0.22 | 0.0285 | 0.169 |
Le Xuan et al. (2020) | 0.61 | 0.0086 | 0.093 |
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Nguyen, N.-M.; Van, D.D.; Le Duy, T.; Pham, N.T.; Duc Dang, T.; Tanim, A.H.; Wright, D.; Thanh, P.N.; Anh, D.T. The Influence of Crest Width and Working States on Wave Transmission of Pile–Rock Breakwaters in the Coastal Mekong Delta. J. Mar. Sci. Eng. 2022, 10, 1762. https://doi.org/10.3390/jmse10111762
Nguyen N-M, Van DD, Le Duy T, Pham NT, Duc Dang T, Tanim AH, Wright D, Thanh PN, Anh DT. The Influence of Crest Width and Working States on Wave Transmission of Pile–Rock Breakwaters in the Coastal Mekong Delta. Journal of Marine Science and Engineering. 2022; 10(11):1762. https://doi.org/10.3390/jmse10111762
Chicago/Turabian StyleNguyen, Nguyet-Minh, Duong Do Van, Tu Le Duy, Nhat Truong Pham, Thanh Duc Dang, Ahad Hasan Tanim, David Wright, Phong Nguyen Thanh, and Duong Tran Anh. 2022. "The Influence of Crest Width and Working States on Wave Transmission of Pile–Rock Breakwaters in the Coastal Mekong Delta" Journal of Marine Science and Engineering 10, no. 11: 1762. https://doi.org/10.3390/jmse10111762
APA StyleNguyen, N.-M., Van, D. D., Le Duy, T., Pham, N. T., Duc Dang, T., Tanim, A. H., Wright, D., Thanh, P. N., & Anh, D. T. (2022). The Influence of Crest Width and Working States on Wave Transmission of Pile–Rock Breakwaters in the Coastal Mekong Delta. Journal of Marine Science and Engineering, 10(11), 1762. https://doi.org/10.3390/jmse10111762