Process of working a metal’s surface to improve its material properties, usually by mechanical means
Performance standards
Statement of the performance required of a structure, system, equipment, person or procedure and that is used as the basis for managing the hazard through the life cycle of the platform
Pre‐stressing tendons
High strength tendons required to maintain the structural integrity of a concrete structure, particularly in the towers (shafts). These tendons are placed in steel ducts, which are grouted following tensioning
Primary structure
All main structural components that provide the structure’s main strength and stiffness
Progressive collapse
The sequence of component failures (from an initial local failure) that will eventually lead to the collapse of an entire structure or large part of it
Push‐over analysis
Non‐linear analysis for jacket structures used for determining the collapse / ultimate capacity
PWHT
Post Weld Heat Treatment
Redundancy
The ability of a structure to find alternative load paths following failure of one or more components, thus limiting the consequences of such failures
Reserve strength ratio (RSR)
The ratio between the design loading (usually 100‐year loading) and the collapse / ultimate capacity
Residual strength
Ultimate global strength of an offshore structure in a damaged condition
Return period
An engineering simplification representing the probability (q) of an event by an assumed average period between occurrences of an event or of a particular value being exceeded. For q less than 0.1 this corresponds approximately to a return period of 1/q years
Risk based inspection
Inspection plans developed from an evaluation of the likelihood and consequences of failure associated with a structure to develop the inspection scope and frequency
Robustness
Measure of the ability of the structure to be damage tolerant and to sustain deviations from the assumptions to which the structure originally was designed
ROV
Remotely Operated Vehicle
RT
Radiographic testing (type of inspection)
Safety critical elements (SCE) and Safety and environmental critical elements (SECE)
Systems and components (e.g., hardware, software, procedures) that are designed to prevent, control, mitigate or respond to a major accident event (MAE) that could lead to injury or death. This was further extended in the 2015 version of the UK safety case regulation to include environmental critical elements
SCF
Stress Concentration Factor
Scour
Erosion of the seabed around a fixed structure produced by waves, currents and ice
Secondary structure
Structural components that, when removed, do not significantly alter the overall strength and stiffness of the global structure
Serviceability limit state (SLS)
A check of functionalities related to normal use (such as deflections and vibrations) in structures and structural components
Sleeve
A sleeve is a concentric tubular surrounding a leg or brace member that is several diameters long. The annular gap between the sleeve and member is normally grouted. In the case of an existing member, the sleeve is necessarily split longitudinally and the two halves are joined during installation using short bolts
SMR
Strengthening, Modification and Repair
SMYS
Specified Minimum Yield Stress
S‐N curve
A relationship between applied stress range (S) and the number of cycles (N) to fatigue failure (regarding fatigue failure, see fatigue limit state)
Splash zone
Part of a structure close to sea level that is intermittently exposed to air and immersed in the sea
SSC
Ship Structures Committee
SPT
Sacrificial pre‐treatment technique (used in adhesive repair)
Station keeping system
System capable of limiting the excursions of a floating structure within prescribed limits
Stress concentration factor (SCF)
Factor relating a nominal stress to the local structural stress at a detail
Structural integrity
A state of being intact and fit for purpose, with an acceptable level of safety against failure
Structural integrity management (SIM)
Means of demonstrating that the people, systems, processes and resources that deliver structural integrity are in place, in use and will perform when required of the whole life cycle of the structure
Structural reliability analysis (SRA)
Method used to analyse the probability of limit state failure of structures
Stud (chain)
Crossbar in the centre of a link of a chain, either welded or mechanically fixed
Studbolt
A threaded rod, generally used in stressed clamps
Subsidence
Settlement of the structure that results, primarily from extraction of reservoir hydrocarbons
