Response Spectrum Method for Extreme Wave Loading With Higher Order Components of Drag Force

• Published in: Journal of marine science and application Vol. 16; no. 1; pp. 27 - 32
• Main Authors: Reza, Tabeshpour Mohammad, Mani, Fatemi Dezfouli, Ali, Dastan Diznab Mohammad, Saied, Mohajernasab, Saied, Seif Mohammad
• Format: Journal Article
• Language: English
• Published: Harbin Harbin Engineering University 01.03.2017; Springer Nature B.V; Center of Excellence in Hydrodynamics and Dynamics of Marine Vehicles, Mechanical Engineering Department,Sharif University of Technology, Tehran, Iran%Department of Marine Industries, Science and Research Branch, Islamic Azad University, Tehran, Iran
• Subjects: Components; Cylinders; Deformation; Drag; Electrical Machines and Networks; Engineering; Extreme waves; Geotechnical Engineering & Applied Earth Sciences; Linearization; Machinery and Machine Elements; Offshore; Offshore drilling rigs; Offshore Engineering; Offshore structures; Power Electronics; Sea surface; Spectra; Steel; Temperature (air-sea); Wave data; 单自由度系统; 变形响应; 基本周期; 曳力; 波浪作用; 海洋结构; 谱方法; 阶分量; offshore structure design; Morison equation; extreme wave; response spectrum method; drag force; wave loading; wave analysis; higher order components
• ISSN: 1671-9433; 1993-5048
• DOI: 10.1007/s11804-017-1397-7

Response spectra of fixed offshore structures impacted by extreme waves are investigated based on the higher order components of the nonlinear drag force. In this way, steel jacket platforms are simplified as a mass attached to a light cantilever cylinder and their corresponding deformation response spectra are estimated by utilizing a generalized single degree of freedom system. Based on the wave data recorded in the Persian Gulf region, extreme wave loading conditions corresponding to different return periods are exerted on the offshore structures. Accordingly, the effect of the higher order components of the drag force is considered and compared to the linearized state for different sea surface levels. When the fundamental period of the offshore structure is about one third of the main period of wave loading, the results indicate the linearized drag term is not capable of achieving a reliable deformation response spectrum.