L51990 Extended Model for Pipe Soil Interaction

This program contributes to maintaining and improving the integrity and safety of existing pipelines with regard to ground movement hazards, and reducing the capital costs of new pipeline systems. The research program focused on the axial, lateral and complex loading of pipeline due to soil movements. It includes (1) a literature review: it presents significant issues related to modeling pipe-soil interaction with a focus to recent development since ASCE (1984); (2) axial loading: it includes a summary of the methods to estimate the axial soil forces on pipeline and recent field measurements on decommissioned pipe sections in weak to desiccated, cohesive to sandy silts in California; (3) lateral loading of buried pipeline: it covers the effects of cover depth, soil strength, loading rate, trench geometry and backfill strength on pipe-soil interaction; (4) complex loading of buried pipeline: the interaction between the lateral and axial soil forces on pipeline are studied; and (5) quantification of mitigative methods: a physical testing program including a total of 20 laterally loaded pipelines are used to identify and quantify the effects of various mitigative methods on reducing lateral loads transferred to a buried pipeline.