A Laboratory Scale of the Physical Model for Inclined and Porous Breakwaters on the Coastline of Soc Trang Province (Mekong Delta)
11/04/2024Abstract:
In the last few decades, the Mekong Delta coastlines have suffered serious erosion. Strong waves during the Northeast Monsoon are one of the main reasons for this. Many types of breakwaters with different structural components have been designed and built to mitigate coastline erosion. Vertical seawalls have been widely used, but they create reflection waves, which can generate water particle kinematics in front of the structure and increase the toe scour. In this study, an innovative block of inclined and porous breakwaters was studied by conducting laboratory-scale experiments. The experimental results show that inclined and porous breakwaters can considerably reduce wave energy due to transmission, reflection, and diffraction compared to inclined breakwaters. The porosity on the front and back sides of the structures has also been studied. Letting sediment-laden seawaters penetrate inside the sheltered zones, porous breakwaters promote accretion and facilitate the forestation of mangrove belts.
1. Introduction
2. Breakwater Block Designs
2.1. Water Level and Wave Condition
2.2. Breakwater Parameters
3. Physical Models
3.1. Modelling Scales
3.2. Model Construction and Scenarios
4. Results and Discussion
4.1. Wave Parameter Estimations
4.2. Dependency of Wave Dissipation Capacity on Pore Diameters of Breakwater
4.3. Wave-Reducing Effects
5. Conclusions
References
1. Zapata, M.U.; Van Bang, D.P.; Nguyen, K.D. Unstructured Finite-Volume Model of Sediment Scouring Due to Wave Impact on Vertical Seawalls. J. Mar. Sci. Eng. 2021, 9, 1440. [CrossRef]
2. Neelamani, S.; Sandhya, N. Wave reflection characteristics of plane, dentated and serrated seawalls. Ocean. Eng. 2003, 30, 1507–1533. [CrossRef]
3. Tofany, N.; Ahmad, M.; Kartono, A.; Mamat, M.; Mohd-Lokman, H. Numerical modeling of the hydrodynamics of standing wave and scouring in front of impermeable breakwaters with different steepnesses. Ocean Eng. 2014, 88, 255–270. [CrossRef]
4. Zanuttigh, B.; van der Meer, J.W. Wave reflection from coastal structures in design conditions. Coast. Eng. 2008, 55, 771–779. [CrossRef]
5. d’Angremond, K.; Van Der Meer, J.W.; De Jong, R.J. Wave Transmission at Low-Crested Structures. In Proceedings of the 25th International Conference on Coastal Engineering, Orlando, FL, USA, 2–6 September 1996; ASCE: Reston, VA, USA, 1997; pp. 2418–2427.
6. Santanu, K.; Panduranga, K.; Almashan, N.; Neelamani, S.; Al-Ragum, A. Numerical and experimental modelling of water wave interaction with rubble mound offshore porous breakwaters. Ocean. Eng. 2020, 218, 108218.
7. Liu, H.-W.; Luo, H.; Zeng, H.-D. Optimal Collocation of Three Kinds of Bragg Breakwaters for Bragg Resonant Reflection by LongWaves. J. Waterw. Port Coast. Ocean. Eng. 2015, 141, 04014039. [CrossRef]
8. Gao, J.; Ma, X.; Dong, G.; Chen, H.; Liu, Q.; Zang, J. Investigation on the effects of Bragg reflection on harbor oscillations. Coast. Eng. 2021, 170, 103977. [CrossRef]
9. Gao, J.; Ma, X.; Zang, J.; Dong, G.; Ma, X.; Zhu, Y.; Zhou, L. Numerical investigation of harbor oscillations induced by focused transient wave groups. Coast. Eng. 2020, 158, 103670. [CrossRef]
10. Le Xuan, T.; Ba, H.T.; Le Manh, H.; Van, D.D.; Nguyen, N.M.; Wright, D.P.; Bui, V.H.; Mai, S.T.; Anh, D.T. Hydraulic performance and wave transmission through pile-rock breakwaters. Ocean Eng. 2020, 218, 108229. [CrossRef]
11. Le Xuan, T.; Le Manh, H.; Ba, H.T.; Van, D.D.; Vu, H.T.D.; Wright, D.; Bui, V.H.; Anh, D.T.Wave energy dissipation through a hollow triangle breakwater on the coastal Mekong Delta. Ocean Eng. 2022, 245, 110419. [CrossRef]
12. Nguyen, N.-M.; Van, D.D.; Le, D.T.; Nguyen, Q.; Pham, N.T.; Tanim, A.H.; Gagnon, A.S.; Wright, D.P.; Thanh, P.N.; Anh, D.T. Experimental modeling of bed morphological changes and toe erosion of emerged breakwaters due to wave-structure interactions in a deltaic coast. Mar. Geol. 2022, 454, 106932. [CrossRef]
13. Chuong, L.T.; Phong, N.C. Computation of Wave and Water Level Combinations for Physical Model Test; Southern Institute of Water Resources Research: Ho-Chi-Minh City, Vietnam, 2019.
14. TCVN-9901:2014; Hydraulic Structures. Sea Structure Design Standard. Available online: http://tlu.edu.vn/Portals/0/CRA/TCVN%209901.rar (accessed on 16 February 2022).
——————————————————————————————————————
Chuong Thanh Le 1, Duong Van Do 1, Duong Binh Nguyen 1 and Ping Wang 2,*
1 Southern Institute of Water Resources Research, Ho Chi Minh City 70000, Vietnam
2 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences,
Beijing 100101, China
* Correspondence: wangping@igsnrr.ac.cn
Water 2023, 15, 1366. https://doi.org/10.3390/w15071366 https://www.mdpi.com/journal/water
Ý kiến góp ý:
