| Summary: | Thesis (M.Eng.)--Memorial University of Newfoundland, 1992. Engineering and Applied Science Bibliography: leaves 176-183 Ice scour is still a phenomena of great concern in the development of offshore oil and gas fields located in a cold ocean environment. Ice scour could also create problems for power cables or pipelines which pass through inland waters such as the Great Lakes. Cables, pipelines, and wellheads are in danger offshore. Direct impact between ice and a subsea installation will most likely cause damage. A seabed installation, such as buried pipeline, might be subjected to additional loading or intolerable displacements through close proximity of an ice keel. The question still remains as to how deep is safe. -- In an attempt to further understand the ice scour process, a series of four physical model tests was carried out at Memorial University's scour tank facility. The first two tests were conducted in a clean, dry silica sand while the remaining two were conducted in the same sand in a submerged state. The objectives of this experimental program were to measure forces and pressures on the model, to measure the response of the soil in the testbed, and, most importantly, to measure displacements in the testbed below the scour. -- The measured results compare well with computed values. The results have also been compared with previous works and models. The analysed experimental results show that there is seabed response and displacement up to 3 1/2 scour cut depths below the unscoured testbed surface. Finally, it was observed that the scouring process was similar for tests in both the dry and submerged state; measured forces and loads less for the submerged tests.
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