The Effect of Coastal Forest on Variations of Broken Wave Force and Inundation Depth

Document Type : Research Paper

Authors

Abstract

Wave breaking in the nearshore zone and then its run up are the main reasons for erosion and destruction of coasts. This causes huge human and financial disasters. Recent coastal protection approaches are based on ecological and environmental balance on the coasts. One of the new coastal protection methods against destruction of waves like tsunami is planting coastal forests that named “coastal green belt”. Coastal forest protection to decrease destruction is based on increasing flow resistance. Therefore, the present study is with purpose of the coastal forest effects on variations of force and inundation of broken waves. For this respect, all of the tests were conducted for 25 heights of incoming waves to Nearshore model with 9% slop in two with and without coastal forest in a flume with length of 8.3m, 0.8 m width, 0.5m height and equipped to a force measurement system. The results of the study show that the coastal forest cause the maximum destructive force and inundation depth of broken waves of an average mitigation of 74 and 40 percent, of 74 and 40 percent, respectively.

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References

1-     چگینی، و. 1377. نظریه­های موج. انتشارات شرکت جهاد تحقیقات آب و آبخیزداری. چاپ اول. تهران. ایران. 301صفحه.
 
2-     راست­گفتار، ا.، اکبرپور جنت، م،ر.، چگینی، و.، رستمی، م. 1391. بررسی آبگرفتگی خلیج چابهار در اثر سونامی ناحیه فرو رو مکران. دهمین همایش بین­المللی سواحل، بنادرو سازه­های دریایی، تهران، ایران.
 
3-      لشکرآرا، ب.، 1388. تعیین تنش برشی در کانال­های مستطیلی با استفاده از روش­های مومنتم و انرژی. پایان­نامه دکتری، رشته سازه­های آبی، دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز، 162 صفحه.
 
4-     نگارش، ح. 1389. سونامی و احتمال وقوع آن در ایران. چهارمین کنگره جغرافیدانان جهان اسلام. زاهدان.
 
5-     هاشمی جوان، س. ع. 1386. شبیه­سازی عددی پدیده شکست موج بر موج­شکن مستغرق. پایان­نامه کارشناسی ارشد. رشته سازه­های هیدرولیکی، دانشکده مهندسی عمران. دانشگاه علم و صنعت. تهران. 116صفحه.
 
6-     Akgul, M. A. Yilmazer, D. Oguz, E. and M. S, Kabdasli. 2013. The effect of an emergent vegetation and wave kinematics. Journal of Coastal Research, 65: 147- 152.
7-     Charvet, I. Eames, I. and T, Rossetto. 2013. New tsunami runup relationships based on long wave experiments. Journal of Ocean Modeling, Elsevier, 69: 79- 92.
 
8-     Davidson, R. G. and B, Greenwood. 2003. Waves and sediment transport in the Nearshore zone. Coastal Zone and Estuarine. Encyclopedia of life support system, 5p.
 
9-     Esteban, M. Thao, D. N. Takagi, H. and T, Shibayama. 2008. Analysis of rubble mound foundation failure of a caisson breakwater subjected to tsunami attack. 18th Offshore and Polar Engineering Conference, Vancouver, 7p.
 
10- Fathi- Moghadam. M. 1997. Momentum absorption in non- rigid, non- submerged, tall vegetation along rivers. University of Waterloo, Canada, PhD. Thesis, 238p.
 
11- Goto, K. and F, Imamura. 2007. Numerical models for sediment transport by tsunami. The Quatren Research, 46(6): 463- 470. 
 
12- Hirashi, T. and K, Harada. 2003. Green belt tsunami prevention in South- Pacific region. Report of the Port and Airport Research Institute, 42(2): 23p.
 
13- Hsiao, C. S. and C. T, Lin. 2010. Tsunami- like solitary waves impinging and overtopping on impermeable seawall: Experiment and RANS modeling. Coastal Engineering, 57: 1- 18.
 
14- Huang, Z., Yao, Y. and S. Y, Sim. 2011. Interaction of solitary waves with emergent, rigid vegetation. Ocean Engineering. 38: 1080- 1088.
 
15- Husrin, S. 2013. Attenuation of solitary wave trains by coastal forests. University of Florence, Germany.PhD. Thesis, 275p.
 
16- Husrin, S., Strusinska, A. and H, Oumeraci. 2012. Experimental study on tsunami attenuation by mangrove forest. Earth Planets Space Journal, 64: 973- 989.
 
17- Malek Mohammadi, S. 2009. Laboratory generation and physics of propagation of solitary waves and water surface depression. University of Clemson, PhD. Thesis, 113 p.
 
18- Oshnack, E. M., Aguiniga, F., Cox, D., Gupta, R. and V. J., Lindt. 2009. Effectiveness of small onshore seawall in reducing forces induced by tsunami bores: large scale experimental study. Journal of Disaster Research, 4(6): 382- 390.
 
19- Ratnosooriya, S. p. and N, Tanaka. 2008. Mitigation of tsunami by coastal vegetation. Journal of the Institute of Engineers, Sri Lanka, Annual Transactions of IESL, PP: 13- 19.
 
20- Suhayda, N. J. and R. N, Petigrew. 1977. Observation of wave height and wave celerity in the surf zone. Journal of Geological Research, 82(9): 1419- 1424.
 
21- Tanaka, N., Sasaki, Y., Mowjood, M. I. M., Jinadasa, N. S. B. K. and S, Homchuer. 2007. Coastal vegetation structures and their function in tsunami protection: experience of the recent Indian Ocean Tsunami. Landscape Ecological Engineering, 3: 33- 45.
 
22- Tanaka, S., Istiyanto, C. and D, Kuribayashi. 2010. Planning and design of tsunami- mitigative coastal vegetation belts. United Educational, Scientific and Cultural Organization. No. 18: 61p
 
23- Thuy, B. N., Tanimoto, K., Tanaka, N., Harada, K. and K, Limura. 2009. Effect of open gap in coastal forest on tsunami run-up – investigations by experiment and numerical simulation. Ocean Engineering. 36: 1258- 1264.
 
24- Yeh, H. 2007. Design tsunami forces for onshore structures. Journal of Disaster Research, 2 (6): 531-536.
Irrigation Sciences and Engineering
Volume 40, 1-1
Special Issue
June 2017
Pages 185-199

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History

  • Receive Date: 22 February 2016
  • Revise Date: 07 June 2017
  • Accept Date: 11 June 2016
  • Publish Date: 01 January 1970

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