STAMUKHA LOADING CASES FOR PIPELINES IN THE CASPIAN SEA

摘要

Ice surveys conducted in the Caspian Sea for the Kashagan Project during the period 2001 to 2010 have shown that stamukhi are frequent enough to create risks to pipelines. This paper reports on work aimed at bounding loads on the seafloor and pipelines due to the grounded ice keels of stamukhi. Gravity loading, as well as forces associated with ice sheet ride-up and subduction during stamukha formation, are considered. The ultimate bound on ice loading on the sea floor is the strength of the ice rubble. Typical pit sizes and depths in various soils due to the estimated ice pressures are calculated. Even if a pipeline is buried below the deepest predicted pits in ambient soils, weak backfill may lead to direct contact of the pipeline by the keel rubble of the stamukha.