St. Marys River Ice Booms - Design Force Estimate and Field Measurements

• Main Author: Perham,Roscoe E
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H
• Format: Text
• Language: English
• Published: 1977
• Subjects: Snow; Ice and Permafrost; *NAVIGATION; *RIVERS; *ICE PREVENTION; DISTRIBUTION; LOADS(FORCES); PIPES; WINTER; BARRIERS; FORCE(MECHANICS); BOOMS(EQUIPMENT); INLAND WATERWAYS; MECHANICAL CABLES; *Ice booms; St Marys River(Michigan and Ontario); St. Marys River; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA037902; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA037902

A set of two ice booms with a 250-ft (76-m)-wide navigation opening between them was designed to stabilize the ice cover in the harbor at Sault Ste. Marie, Michigan and Ontario, and to reduce the ice losses associated with winter navigation of ships on the St. Marys River. The forces from natural effects on the ice cover were predicted using existing theory and physical data for the area. The forces in the boom structure resulting from ice cover and boom interaction were estimated. When the ice booms were installed, force measurement systems were put into selected anchor cables. These systems were operated all winter in conjunction with a modest program of supplemental data gathering. The force data exhibited periods when the force distribution was in good agreement with predictions and periods when the effect of the ice on the booms differed substantially from predictions. Sometimes passing ships had a substantial effect on the ice cover and the boom loads, and at other times, the effect was negligible. The direction of travel made little difference on average peak loads. The maximum loads on the booms resulted from natural occurrences.