Determine the Load and Dominant Wave Spectrum in the Design of the Jackets in Terms of Base Shear

Determining the dominant force in Jacket design is often one of the main concerns of engineers. In the current study, a marine jacket with a height of 50 meters, with an effective 6 m wave height and a deck height of 10 meters is considered hypothetically. These dimensions is in accordance with the general conditions of the Persian Gulf. The wind load, the regular wave and the random wave load have been applied under the Pierson-Moskowitz, Bretschneider, Mitsuyasu and JONSWAP spectra to the considered jacket and for all stages the jacket base shear has been obtained by using the STRUCAD software. Based on the results obtained in terms of base shear, the random wave with the JONSWAP spectrum yielded the highest base shear and compared to the Pierson-Moskowitz spectrum, 11%, Bretschneider 17%, Mitsuyasu 19%, Regular wave 27%, and wind load 38%, provides more base shear. Thus, due to the lack of sufficient field information in the design of Jackets in terms of base shear, it is recommended to use the JONSWAP spectrum.