Ice Loads and Ship Response to Ice. A Second Season

• Main Authors: Daley, C., St John, J. W., Brown, R., Meyer, J., Glen, I.
• Other Authors: ARCTEC INC COLUMBIA MD
• Format: Text
• Language: English
• Published: 1990
• Subjects: Snow; Ice and Permafrost; Marine Engineering; *VELOCITY; SHIPS; IMPACT; DATA MANAGEMENT; VALIDATION; BEAUFORT SEA; ICE; RESPONSE; PRESSURE; SUMMER; FITTING FUNCTIONS(MATHEMATICS); SEASONS; MATHEMATICAL MODELS; FINITE ELEMENT ANALYSIS; *ICE LOADS; *ICE BREAKERS; *SEA ICE; MULTILAYER ICE; LOADS(FORCES); Psi; Beaufort Sea; Ice; permafrost; Sea ice
• Online Access: http://www.dtic.mil/docs/citations/ADA231528; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA231528

A total of 337 events were collected in the Beaufort Sea in summer multiyear ice conditions. Ship impact speed ranged from 0.5 to almost 6 kts. Ice conditions were generally less severe resulting in lower loads than in 1982. Extremes of the data showed a single sub-panel pressure as high as 1041 psi (7.2 MPa) and a maximum total panel force of 374 LT (380 MT). This pressure and force are about 65 and 75%, respectively, of those recorded on the previous deployment to the Beaufort Sea in 1982. Conclusions from the study are: (1) Speed effects were not apparent in the single sub-panel pressure data and only weakly evident in the total force data. (2) Total force and pressure data fit a Gumbel probability distribution for the events collected (337 events). Known multiyear data also fit a Gumbel distribution except for the single sub-panel pressure which fit a Frechet distribution, though there is a very small number of events. (3) Loading the panel with known forces, as was performed in 1982 for validation of the finite element model, showed no significant differences in the measured response.