Whole-life geotechnical design couples the life cycle of imposed actions with geotechnical resistance that may evolve over the life of the structure, to forecast the soil-structure response across the design life. Changes in seabed resistance, from changes in seafloor profile and seabed properties from loading events during the life of a structure, affect the response of the seabed and the structure to a future event. Allowing for these changes can have a beneficial design outcome. Greater scrutiny of the whole-life loading, soil-structure interaction and the associated seabed response, offers efficiencies over traditional design methods that use a single value of a geotechnical property. Application of whole-life design principles provides insight into the response of geotechnical infrastructure over the whole design life, and for the end of engineered life. Not only does whole-life geotechnical design offer more accurate prediction of soil and structure response throughout the design life, it offers opportunities for more efficient systems. Benefits include reduction in infrastructure size, therefore easing installation and minimizing embodied energy; reduced risk of fatigue; greater insight for late life management; and informed decommissioning processes for offshore infrastructure. This paper introduces the philosophy of whole-life geotechnical design (the What?), presents drivers and applications (the What For?) and potential impact (the So What?) through practical examples. The paper closes with a discussion of next steps to enable whole-life geotechnical design to be more readily adopted in routine practice where appropriate (the What Next?).
Susan Gourvenec
Keywords: offshore, geotechnics, design, whole-life
Publisher: DFI