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Hydraulic Model Experiments and Performance Analysis of Existing Empirical Formulas for Overtopping Discharge on Tetrapod Armored Rubble Mound Structures with Low Relative Freeboard

상대여유고가 낮은 테트라포드 피복 경사제의 월파량에 대한 수리모형실험 및 기존 경험식의 예측성능 분석

  • Sang-Woo Yoo (Dept. of Civil Engineering, Korea Maritime and Ocean University) ;
  • Jae-Young Kim (Dept. of Civil Engineering, Korea Maritime and Ocean University) ;
  • Do-Sam Kim (Dept. of Civil Engineering, Korea Maritime and Ocean University) ;
  • Kwang-Ho Lee (Dept. of Civil Engineering, Korea Maritime and Ocean University)
  • 유상우 (국립한국해양대학교대학원 토목환경공학과) ;
  • 김재영 (국립한국해양대학교대학원 토목환경공학과) ;
  • 김도삼 (국립한국해양대학교 토목공학과) ;
  • 이광호 (국립한국해양대학교 토목공학과)
  • Received : 2024.05.28
  • Accepted : 2024.06.12
  • Published : 2024.06.30

Abstract

In coastal structure design incorporating revetments, the assessment of wave overtopping discharge relies on hydraulic model experiments. Numerous empirical formulas have been developed to predict overtopping discharge based on quantitative data from these experiments. Typically, for revetment structures aimed at mitigating wave overtopping, crest height is determined by considering the maximum amplitude of the design wave, resulting in a relatively high freeboard compared to wave heights. However, achieving complete prevention of all wave overtopping would require the crown wall to have substantial crest heights, rendering it economically impractical. Therefore, the concept of limiting discharge has been introduced in the design of revetment structures, aiming to restrict wave overtopping discharge to an acceptable level. Consequently, many coastal structures in real-world settings feature relatively lower freeboard heights than incident wave heights. This study investigated wave overtopping discharge on rubble-mound breakwaters with relatively low freeboard heights through hydraulic model experiments. Furthermore, it conducted a comparative analysis of the predictive capabilities of existing empirical formulas for estimating overtopping discharge using experimental data.

호안을 포함한 해안구조물의 설계 시 월파량 평가는 주로 수리모형실험에 의존하며, 이를 기반으로 월파량 예측을 위한 많은 경험식이 제안되었다. 일반적으로 월파방지를 위한 호안구조물의 경우 설계조위에 설계파의 최대 수면진폭을 고려하여 마루높이가 결정되므로 입사파고에 비해 상대적으로 높은 여유마루고를 갖는다. 그러나, 월파를 원천적으로 차단하기 위해서는 비경제적인 구조물의 마루높이가 요구되기 때문에 호안구조물의 설계 시 월파량을 허용 가능한 수준으로 제한하는 허용월파량의 개념을 도입하고 있다. 따라서, 실해역에서는 입사파고에 비해 상대적으로 낮은 여유마루고를 갖는 호안구조물들이 존재한다. 본 연구에서는 수리모형실험을 통해 상대적으로 낮은 여유마루고를 갖는 사석경사제의 월파량에 관해 검토하였다. 또한, 월파량의 실험결과를 이용하여 기존 월파량 산정을 위한 경험식의 예측성능을 상호 비교·분석하였다.

Keywords

Acknowledgement

본 연구는 해양수산과학진흥원(KIMST)의 "월파 정량 관측기술 개발(20220180)" 사업의 지원을 빋아 수행된 연구이며, 연구비 지원에 감사드립니다.

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