| Summary: | In regions which experience arctic conditions, structures like offshore wind turbines, oil-platforms, light houses, piers and bridges suffer from abrasion by moving ice sheets. This results in challenging maintenance and repair works. At the ice-structure interface, several mechanisms exist which are responsible for the wear of concrete such as: freeze-thaw cycles, chemical effects of sea water, and mechanical loading of concrete. The main cause of concrete abrasion is however thought to be the flow of ice floes together with a layer of crushed ice, which is partly controlled by friction and adhesion between the two interfaces. Adhesion is thought to be the main component of the static friction and is, under certain circumstances, also directly responsible for concrete abrasion. It is yet not well known to what degree ice adhesion contributes to concrete abrasion, and how extrinsic parameters such as: pressure, hold time and submergence relate to the ice-concrete bond strength. This research aims to better understand the physical phenomena happening at the ice-concrete interface by shearing an adhesive ice-concrete bond to get a better understanding of the role of ice adhesion in concrete abrasion processes. To achieve this goal, a double shear apparatus has been designed and ice-concrete shear tests have been performed in a thermal laboratory. The apparatus was designed to be relatively simple compared to conventional soil shearing machines. The design allowed for the ability of submergence, accurate and sustained application of normal load, improved implementation of standardisation procedures, and easy portability. The temperature during the test was remained relatively constant at around - 9° for dry the ice-concrete adhesion test, and around 0° C for submerged tests. The influence of hold time, varying from very short (6 seconds) to overnight, and pressure (51, 316 and 682 kPa) on the force required to break the ice-concrete bond has been investigated following a series of five test sequences. In sequence ...
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