Load attenuation through grounded ice rubble at Tarsiut Island

• Main Authors: Timco, Garry, Wright, B.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 1999
• Subjects: Arctic; Beaufort Sea; Ice Sheet
• Online Access: https://nrc-publications.canada.ca/eng/view/accepted/?id=aeb51a2e-394c-4e9f-8e6b-448f49a59c5f; https://nrc-publications.canada.ca/eng/view/object/?id=aeb51a2e-394c-4e9f-8e6b-448f49a59c5f; https://nrc-publications.canada.ca/fra/voir/objet/?id=aeb51a2e-394c-4e9f-8e6b-448f49a59c5f

The Tarsiut Caisson Retained Island (CRI) was the first caisson island used for exploratory drilling in the Canadian Beaufort Sea. During the winter of 1982/83, it was used as a test platform to measure ice loads on Beaufort Sea structures, as part of the Tarsiut Ice Research Program (TIRP). The Tarsiut CRI was a hybrid sand and concrete caisson structure that was approximately 100 m wide. It was deployed on a large sand berm in a relatively shallow water depth of 20 m. During the TIRP program, a large grounded rubble field formed around the CRI. A number of different parameters were measured throughout the winter as part of TIRP, including the ice loads, ice conditions, and general movement of the ice. In the spring, a number of strain-measuring devices were used to measure the strains in the ice sheet surrounding the grounded rubble field. From this information, loads could be determined both on the outer edge of the grounded rubble field and at the caisson structure itself. There were a few significant ice-loading events during this particular deployment. In all cases, the ice load directly measured on the caisson was substantially lower than the load on the outer edge of the grounded rubble field surrounding it. This paper presents a brief overview of the test program and the measuring systems at Tarsiut. Three significant ice-loading events are described in detail and the attenuation of the ice load through the grounded ice rubble is described. It is seen that the grounded ice rubble acted as a protective barrier. The average global load was attenuated by more than 60% due to the presence of the rubble. The peak global load was attenuated by 85%. NRC publication: Yes