scope:

This recommended practice gives recommendations on how to evaluate pipe-soil interaction in various design situations or assessments relevant to exposed and buried submarine pipelines.

The recommendations are primarily related to the interaction between the pipeline and soil per unit length of the pipeline. The following topics are covered:

- required soil and pipeline properties for pipe-soil interaction assessments

- pipeline embedment

- pipe-soil interaction considerations for exposed and buried/covered pipelines

- treatment of uncertainties related to pipe-soil interaction assessments

This recommended practice does not consider the following topics:

- geohazards

- earthquake design and assessment of pipelines

- riser-soil interaction

- pipeline-soil-structure interaction

- pipelines on exposed bedrock.

Further, the full interaction between the pipe and soil, accounting for the stiffness of the pipe and the loads acting upon the pipe, is not covered in this recommended practice other than as brief discussions where relevant, with references to other relevant recommended practices.

Likewise, the integrated interaction between a pipeline or flowline, including spools and connected structures, is covered in respective standards or recommended practices for pipelines and structures. The recommendations given herein may be used as input for analysis of such integrated interaction.