Model test for studying ice forces on jack-up structure

In order to study the ice force on jack-up structure which has cylindrical leg with gear teeth, a series of model tests are conducted to compare the ice forces on two cylindrical indentors of the same diameter, one of which has gear teeth on both, sides scaled from the prototype jack-up platform and the other has no gear teeth. Results of the model, tests indicated that ice forces on the jack-up indentor vary slightly when, the angle between ice moving direction and gear teeth direction changes, which accords with prediction before test. However, the gear teeth did not increase magnitude of ice force significantly, which means that ice load formulation of jacket platform could be applied to jack-up structure. On the other hand, ice induced steady state vibration and lock-in between structural response and dynamic ice force still exist on jack-up structure, which attributes to the nearly same crushing failure on jacket platforms here. Copyright © 2010 by The International Society of Offshore and Polar Engineers (ISOPE).