Downstream Transition of River Ice Jams

Abstract

The granular mass theory of river ice jams is extended to their downstream transition as a means of improving understanding of conditions at jam toe. The theory is coupled with the equations of motion under, and seepage through, the jam and the resulting differential equations are solved numerically. The present model applies to wide rectangular channels and involves several coefficients whose precise values in nature are unknown. Example calculations are performed to illustrate the sensitivity of the model to the various coefficients. Preliminary application of the model to two case studies resulted in plausible findings with regard to grounding of ice jams.