Journal of the Korean Society of Hazard Mitigation (한국방재학회 논문집)

Korean Society of Hazard Mitigation (한국방재학회)
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Effects of Disaster Prevention of a Coastal Forest considering Wave Attenuation Ability

파랑의 감쇠 특성을 고려한 해안림의 방재효과

  • 이성대 (한라대학교 토목공학과) ;
  • 김문정 (한라대학교 산업대학원)
  • Received : 2014.07.03
  • Accepted : 2014.09.02
  • Published : 2014.10.31
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Abstract

Recently, it has been widely recognized that coastal forests may have great value in protecting from wave attack, forming sand dunes and maintaining good scenery. Utilizing coastal forests as a countermeasure against storm surges or tsunamis has attracted engineers, because coastal forests have concurrent benefits both of disaster prevention and environmental preservation. This study investigates the morphologic properties of coastal trees which will act as hydrodynamic resistance against incident wave. Then, a numerical analysis based on the CADMAS-SURF model has been conducted. Wave attenuation due to the drag, porosity and width of coastal forests are well reproduced by the present numerical simulation. Comparison between with and without coastal forest model have revealed that the phases of water surface fluctuation and horizontal velocity proceed when the coastal forest model exists. The results show that the 60 m width of coastal forest was formed, the velocity was decreased by 36%, the energy flux by 2%. Therefore, it has been investigated that the affimative conclusions on the protective role of coastal forest against storm surges and tsunami.

연안식생은 파랑으로부터 배후 공간을 보호하고 해안 침식을 감소하며 아름다운 자연경관을 제공하는 등 최근 연안에서의 식생 가치가 재인식 되고 있다. 해안방재림은 연안 방재 및 해안 환경 보전의 측면에서 뿐만 아니라 폭풍해일이나 지진해일 등에 대한 대책법으로 관심의 대상이 되고 있다. 본 연구에서는 입사파에 대한 해안수리학적 특성을 파악하기 위해 먼저 해안림의 형태학적 특성을 조사하였다. 그리고 CADMAS-SURF 모형을 통해 수치 해석을 수행하였으며, 해안림의 항력계수, 공극율 및 해안림 폭 등에 따른 입사파의 감쇠특성을 대체로 잘 예측하였다. 그리고 해안림이 있는 경우와 없는 경우에 대해 수위, 수평유속 및 에너지플럭스의 변동에 대해 비교하여 검토하였다. 검토결과 해안림을 60 m 폭으로 조성하면 수평유속은 36%, 에너지플럭스는 2%로 저감되는 것으로 니타나 폭풍해일이나 지진해일에 대한 해안림의 방재효과를 확인하였다.

Keywords

Acknowledgement

Supported by : 한라대학교

References

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  2. INSTALLATION PARAMETERS EFFECTING ON THE WIND PROOF OF A COASTAL FOREST vol.20, pp.2, 2015, https://doi.org/10.6112/kscfe.2015.20.2.052