BEND ICE JAMS - LABORATORY OBSERVATIONS

Presented herein are the results of laboratory experiments aimed at obtaining preliminary insights into characteristic features of ice jams in river bends. The experiments, which focused on jams comprising a continuum of ice pieces small compared to river width, were carried out using a curved flume and polypropylene beads to simulate ice pieces. They revealed that jam thickness was greatest along the inner bank, and especially in the lee, of a bend. In many respects, jam-thickness distribution was found to be analogous to alluvial bed topography. Additionally, flow in the jam-covered bend flume was found to develop a double helicoidal flow pattern which resembled mirror-image combinations of flow field associated with openwater flow in alluvial bends.