Ice Rubble Behavior in Punch Tests

Abstract

This paper summarizes the results of a series of punch tests conducted on freshwater ice rubble at the University of Calgary. The main objective of the tests was to approximate the in situ punch tests in such a manner that failure behavior of the ice rubble and the effect of different parameters could be studied. The tests were conducted in a rectangular Perspex tank, which simulated the plane strain mode and made it possible to observe and record the failure process. The first set of tests provided considerable insight into the behavior of rubble ice, but it was clear that a more rigorous test program was required. For the second test series, the equipment was improved so that it provided a better control over speed and less fluctuations in the recorded loads. A summary of the collected data regarding the strength properties is presented and the observed behavior is discussed. It is concluded that using video photography and a 2D test arrangement has provided invaluable insights into the behavior of ice rubble. These included the observation that the failure behavior depended on the loading rate. The observations obtained from the low-speed tests support the use of geotechnical anchor plate theories for the interpretation of these results.