Dnv-rp-f118 //top\\ Guide

Short summary — key points from DNV‑RP‑F118

Scope: Methods to estimate ice loads on ships, offshore structures and marine installations in level ice and broken-ice conditions for design and assessment.
Ice properties: Classification of ice types, typical mechanical properties (compressive strength, flexural strength, Young’s modulus) and how temperature, salinity and grain structure affect them.
Load-generating mechanisms: Descriptions of failure modes (flexure, crushing, splitting, bending, indentation) and interaction scenarios (continuous drift, grounded ice, ridges, icebergs).
Design ice thickness and statistics: Guidance on selecting representative ice thickness, return periods, and using probabilistic approaches for extreme-event loads.
Deterministic load models: Empirical and semi-empirical formulas for local and global ice pressures, bearing capacity, and ice-structure contact pressure distributions.
Probabilistic methods: Treatment of uncertainties in ice properties, encounter frequency, and variables; methods to derive characteristic loads for target reliability levels.
Dynamic interactions: Consideration of relative motions, velocity effects, and energy dissipation during ice impacts.
Numerical modelling: Recommendations for using FEM, discrete-element and other computational models; calibration and validation against tests/field data.
Testing and validation: Recommended laboratory and field tests for deriving parameters and validating models (compression, bending, indentation, model-scale interaction tests).
Safety and design checks: Suggested acceptance criteria, load combinations, and considerations for inspection, monitoring and operational mitigation.

Quality Assurance: Assessing the manufacturer's systems for maintenance and software updates.

Weld Repair Limits: No more than 20% of wall thickness and 50mm length without re-qualification.
Cold Bending vs. Hot Induction Bending: Different allowable strain limits (typically 2.5% for cold field bends, 5% for hot bends).
Hydrostatic Testing: 1.25 x design pressure for 4 hours; no yield or leakage.

that provides a rigorous framework for the qualification and project-specific validation of AUT systems. It serves as the practical bridge to the requirements found in DNV-ST-F101 Appendix E dnv-rp-f118

Statistical Analysis: Generating PoD and sizing accuracy curves to prove the system meets the project-specific Acceptance Criteria. The Role of Simulation (CIVA) Short summary — key points from DNV‑RP‑F118