Large longitudinal strains may be generated by a number of sources. The most relevant events for onshore pipelines are seismic activities and arctic hazards. The determination of strain demand can be a very complex undertaking involving multiple disciplines such as geology, seismology, soil mechanics, and soil and pipe interaction.
Seismic activities (earthquakes) can cause permanent ground deformation from liquefaction, surface-faulting, and landslides. Transient ground deformation may occur from the wave propagation of earthquake induced ground shaking. In arctic environment, high longitudinal strains may arise from frost heave and thaw settlement and from ice scouring.
CRES treats the strain demand as an integral element in SBD. Our comprehensive approach combining the ground/soil movement with pipe material response ensures consistency between strain demand and strain capacity.