PR-214-154503-R01 Pipeline Strains Induced by Slope Movement

Pipeline integrity may be affected by the action of the external soil loads that can be generated by ground movements or slope failures and the structural integrity threat of these geotechnical failures is not well understood. The threat presented to a pipeline by a localized slope failure is not directly related to magnitude of the soil movement involved, but related to the stress and strains induced in the pipeline by the moving soil block. This project demonstrated and applied advanced pipe-soil interaction numerical modeling tools in the assessment of slope movements directed long the pipeline axis. The geotechnical hazard assessments completed in this project provide a conservative means of estimating the pipeline axial strain accumulation resulting from slope movements. These modeling results are presented such that an understanding of the influence of pipeline, slope and operational parameters on strain accumulation is demonstrated and the relative importance of each parameter is demonstrated. The relationship between surface expression of a geotechnical event and the subsurface parameters to facilitate conservative characterization of the event is defined. The data describing axial strain as a function of ground movement magnitude presented in this project may be compared to the axial strain capacity (resistance) engineering tools to evaluate the significance of slope movements on pipeline integrity.