Touchdown Analysis of Jack-Up Units for the Definition of the Installation and Retrieval Operational Limits

The paper presents the development of a methodology for the definition of the operational limits for Self-Elevating Units, during the “jack-up” and “jack-down” operations. The methodology is based on the structural analysis of the unit during the impact between the spud can and the soil. The mechanics of the impact is based on the first principle of Momentum Theory and the Virtual Work Theory. The study includes the development of a motion analysis in order to obtain the allowable maximum wave heights that guarantee the integrity of the unit.