Assessments on Effectiveness of Coastal Bio-shield for Reduction of the Energy of Storm Surges

Authors

  • Md. Arifur Rahman Bangladesh University of Engineering and Technology

Keywords:

Coastal Bio-Shield, Numerical Model Simulation, Laboratory Experiment, SPOT Image, SIDR

Abstract

Vegetation bio-shield has been widely recognized as a natural method to reduce the energy of cyclones and storm surges. The effectiveness of coastal vegetation in reducing storm surge has been investigated in this study. This study includes three types of analysis such as satellite image analysis, numerical model simulation and laboratory experiment. In satellite image analysis, two SPOT images are analyzed to investigate the damages caused by the super cyclone SIDR occured on the 15th of November, 2007. From this analysis it is studied that the densely populated vegetation areas were less damaged than the exposed areas without vegetation barriers. About 3% of the total study area was damaged by the cyclone SIDR. A two dimensional hydrodynamic model named Bay of Bengal model was applied for Sandwip island to study the effect of afforestation in reducing storm waves and current speed. Three scenarios of 200m, 400m and 600m distance of vegetation  from embankment and two specific points were considered at the east side of Sandwip island. Results show that the water level decreases slightly but the current speed increases significantly as the distance of vegetation barrier increases from the embankment towards the sea. The laboratory experiment shows that the wave height is reduced up to 46% behind the vegetation zone, 43% within the barrier and 41% in front of vegetation for wave period of 1.6 sec when the vegetation barrier is placed at 1m from embankment.

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Published

2013-04-21

How to Cite

Rahman, M. A. (2013). Assessments on Effectiveness of Coastal Bio-shield for Reduction of the Energy of Storm Surges. Asian Journal of Engineering and Technology, 1(1). Retrieved from https://ajouronline.com/index.php/AJET/article/view/89

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Section

Articles