Dynamic analysis of an underwater leveling-gripping system of an jacket platform under offshore environmental loads

This paper concerns dynamic analysis of an underwater leveling-gripping system which is mounted on a jacket under the influence of offshore environmental loads. Based on the Shinozuka theory, the wave load is calculated in the time domain while the ocean current and wind load on the jacket structure are calculated as constant loads. The main environmental loads and its combination which jacket withstand in leveling process are therefore defined. Using SACS software, according to the South China Sea conditions, a platform bottom dynamic response is calculated under extreme environmental loads in different return period. ADAMS software is also used to dynamically analyze the contact force of key clamping contact parts of leveling-gripping system in leveling process. With the result of analysis, the influence of environmental loads on leveling-gripping system, changes with time, can be obtained accurately, which is an important basis for the design of key parts of the leveling-gripping system.