DNV-RP-F105 Free spanning pipelines

Recommended practice

Edition 2025-12

This recommended practice (RP) specifies requirements and guidance for ultimate limit state (ULS) and fatigue limit state (FLS) due to in-line and cross-flow vortex induced vibrations (VIV) and direct wave loading. The following topics are covered:

  • Methodologies for free span analysis
  • Environmental conditions
    • Steady flow due to current
    • Oscillatory flow due to waves
    • Combined flow due to current and waves
  • Structural and modal response modelling and calculations
  • Categorization of free spans
  • VIV response
  • Direct wave action response
  • Application of sensor technology
  • Acceptance criteria, including VIV avoidance, simplified and detailed fatigue assessments.