Author(s): Megan O’Sadnick; Chris Petrich; Bard Arntsen; Bjornar Sand
Keywords: No Keywords
Abstract: From October 2014 to June 2015, ice stress was measured at Taraldsvikfossen reservoir in Narvik, Norway. Three frames composed of five stress sensors placed vertically at 0.15 m intervals were attached to the dam 6.0 m apart. During this time, compressive and to a lesser degree tensile stresses were observed primarily in the range of±100 kPa. However, measurements exceeded this range on several occasions. The magnitude and timing of the peaks in stress depended on vertical position with the upper three sensors often displaying opposite behavior of the lower two sensors. We analyze two main events of high stress to determine the likely cause and enhance our understanding of the ice dynamics exhibited. The influences of water pressure and ice temperature are examined in depth to delineate between mechanical and thermal stresses during each event. Our findings demonstrate the strong influence of loading due to mechanical processes with the fracture of ice and flooding of the ice surface represented clearly in the data. The challenges that exist in modeling and predicting ice loading are discussed alongside considerations to be taken into account for data interpretation and further measurements.