You use the SIFs tab to specify the Stress or Strain Intensity Factors (SIFs) on the pipe section for postprocessing, including fatigue analysis. SIFs are increases in the bending stress or bending strain of the pipe section that are caused by, for example, stiffness differences.
Note
This tab is not available in PipeLay Starter Edition
SIFs Tab
The SIFs tab contains two buttons; Constant and Variable as shown in the 'SIFs Tab' figure above. When you click on the Constant button, the SIF Constant – Define dialog is displayed as shown in the 'SIF Constant' figure below. You use this dialog to specify a constant SIF value for the pipe section.
SIF Constant
When you click on the Variable button, the SIF Variable – Define dialog is displayed as shown in the 'SIF Variable' figure below. You use this dialog to specify SIFs whose magnitude varies as a function of the bending strain.
SIF Variable
If you specify a constant SIF, PipeLay factors both the bending stresses and bending strains on the pipe section during all types of postprocessing and fatigue analysis. If you specify a variable SIF, PipeLay factors the bending strains only on the pipe section. Note that SIFs form part of the PipeLay model and so should be defined prior to running a full analysis. If SIFs are defined after the full analysis has been run then they may not take effect during subsequent postprocessing only runs.