Title Local ice pressures for multiyear ice accounting for exposure
Author Jordaan, I.; Bruce, J.; Masterson, D.; Frederking, R.
Author Affil Jordaan, I., Ian Jordaan & Associates, Canada. Other: C-CORE, Canada; Chevron Canada, Canada; National Research Council of Canada, Canada
Source Cold Regions Science and Technology, 61(2-3), p.97-106, . Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0165- 232X
Publication Date May 2010
Notes In English. Based on Publisher- supplied data; includes appendix GeoRef Acc. No: 309576
Index Terms design; exposure; ice; loading; offshore structures; pressure; structures; Arctic Ocean--Beaufort Sea; Arctic Ocean-- Chukchi Sea; Amauligak Field; Arctic Ocean; Beaufort Sea; Chukchi Sea; marine installations; Molikpaq Platform; offshore; oil and gas fields; ship rams
Abstract Local pressures are generally determined based on extreme pressures obtained in measurements. The exposure of structural components is an issue that needs attention. Exposure can be considered in everyday terms as "the longer you fish, the bigger the fish you catch." In the case of design of offshore structures for ice environments, the more numerous the number of ice-structure interaction events, the greater the likelihood of a particular load being exceeded. The number of interactions with multiyear ice is different for say the Beaufort and Chukchi Seas, and varies with location within these areas. These differences are expressed in terms of the exposure of the structure to multiyear ice. Exposure may also vary depending on location within the structure. Structure above or below the ice belt may receive few interactions resulting in small local pressures. The paper presents a generalization of a method for accounting for exposure, originally developed for ship rams. The particular application is multiyear ice interacting with a structure. The panel data from the Beaufort Sea experience of the Molikpaq structure is used as an example. Exposure is an important parameter that can be taken into account with the method. The previous relationship alpha =1.25a-0.7 obtained for ship rams can be reasonably applied to multiyear ice, where 10 min of multiyear ice interaction is approximately equivalent to 1 Kigoriak ship ramming event. The method is promising for use in codes, for example with the new ISO Code 19906.
URL http://hdl.handle.net/10.1016/j.coldregions.2009.12.008
Publication Type journal article
Record ID 65006532