천해역 경사 천퇴에 설치된 해양구조물의 층하고 검토를 위한 수치해석 - 가거초 종합해양과학기지의 태풍피해 (2011)

Abstract

The design wave and deck clearance of an offshore structure are very important factors to secure the stability of the structure after construction. In case that the structure is installed on a deep flat bottom, the deck clearance may be determined from the maximal wave crest height which can be sought by directly applying a nonlinear wave theory (Cnoidal or Stream function theory) to the design wave condition. But it is often the case that the structure is placed on a shallow underwater shoal having a steep slope due to construction expense and convenience. In this case, the wave height and depth conditions at the structural position may easily exceed the wave breaking condition beyond which the nonlinear wave theory cannot be applied. In the present study, a numerical method using a shallow water wave propagation model based on Boussinesq equation is demonstrated to reproduce the nonlinear wave deformation along up the shallow underwater shoal and the maximal wave crest height at the structural position. The method is applied to check the validity of the existing deck height of Gageocho Ocean Research Station installed on an underwater shoal in Korea. The station was damaged by typhoon Muifa in 2011 with the cellar deck and its appurtenance seriously deformed or destroyed.