In-place strength assessment of a jacket and effects of an impact with a floating living quarter (flotel)

Abstract

The primary function of a jacket structure is to support the weight of the topside structure by transferring the weight to the foundation. The jacket structure must also be designed to resist environmental loads (from wind and waves) and also accidental loads, such as boat impact, extreme environmental conditions and earthquake. This thesis presents the results from a strength assessment based on the conceptual design of an eight-legged jacket with V plus X braces pattern and an alternative six-legged jacket with fully X braces pattern. Subsequently, a study was carried out to compare the responses of the two jacket structures when they are subjected to an accidental collision from a floating living quarter (a flotel). To date, extensive research has been carried out on vessel-to-jacket collisions. However, little work has been performed for flotel-to-jacket collisions. This thesis implements the basic design principles of ship collision and several reasonable assumptions. It is expected that the results could provide an overview of how the different potential impact locations and directions will influence the resistance capacity of the jackets. It is also anticipated that this procedure and the assumptions could be a reference for related research in the future.