Det Norske Veritas - Germanischer Lloyd

DNVGL  Structural design of self-elevating units - LRFD method
 N DNVGL-OS-C104

Annotation

Scope and application

All marine operations shall, as far as practicable, be based upon well-proven principles, techniques, systems and equipment and shall be undertaken by qualified, competent personnel possessing relevant experiences.

A self-elevating unit is designed to function in a number of modes, e.g. transit, operational and survival. Design criteria for the different modes shall define and include relevant consideration of the following items:

— intact condition, structural strength

— damaged condition, structural strength

— fatigue strength

— accidental damage

— air gap

— overturning stability

— watertight integrity and hydrostatic stability.

Limiting design criteria when going from one mode to another shall be established and clearly documented.

Serviceability (SLS) condition is not covered in this standard.

For novel designs, or unproven applications of designs where limited or no direct experience exists, relevant analyses and model testing, shall be performed which clearly demonstrate that an acceptable level of safety is obtained.

Self-elevating units shall be based on environmental conditions specified by the designer. Worldwide service operation is not applicable.