A Conceptual Model for Vertical Frazil Distribution in Turbulent Flows
A conceptual model is presented for the evolution of frazil over depth in a turbulent flow. The net upward migration due to buoyancy of the frazil is opposed by intermittent mixing induced...
Heat Exchange at the Ice/Water Interface on Flowing Water
Any time the water flowing under an ice cover has a temperature above freezing, there is an exchange of heat between the water and the ice. Earlier work by Ashton and others provided adequate...
A Two-Dimensional Surface Drift Model for River Ice
A two-dimensional surface drift model for river ice with low ice discharge conditions is presented. The model is applied to the Grass Island Pool area of the Niagara River and compared...
River Ice Cover Cracking for Various Boundary Conditions
The breakup of river ice covers is commonly initiated by the formation of cracks parallel to river banks. These cracks usually result from a change in the water level due to a rapid rising...
The River Ice Management (RIM) Program: Developing New Options for Waterways Operations in Winter
Most of the navigable inland waterways of the United States are utilized year-round. In northern portions of this network (mainly parts of the Ohio and Upper Mississippi River basins),...
Designing for Control of Ice Conditions in Marinas
Each marina or small-craft harbor experiencing ice during the winter months must be designed for site specific conditions. These conditions are governed by environmental factors (geology,...
A Shallow-Draft Icebreaker for the Upper Niagara River
The New York Power Authority (Authority) designed and built a special purpose, shallow-draft icebreaker in 1986 and 1987 for use in the upper Niagara River. The icebreaker is used during...
Radar Monitoring of Ice on the Upper Niagara River
A standard marine radar was used during the winter of 1987-88 to evaluate its potential to monitor the presence and movement of ice in the Grass Island Pool area of the upper Niagara River....
Future Technology for Disbonding Snow and Ice from Pavements
Current techniques to remove ice and compacted snow from pavement surfaces are costly because they needlessly crush or melt most of the ice layer. Also, in many cases they do not accomplish...
On the Constitutive Behavior of Single Ice Crystals Due to Dislocation Mechanisms
A three-dimensional constitutive relation is derived for single ice crystals. The formulation is developed in terms of dislocation processes on the basal, prism, and pyramidal planes....
Visco-elasticity and the Compressive Failure of Polycrystalline Ice
The analysis of the visco-elasticity of polycrystalline ice is addressed. Experimental results on isotropic and anisotropic polycrystalline ice are presented, which indicate that intracrystalline...
Anelastic Straining in Polycrystalline Ice
This paper presents experimental observations on the influence of stress, grain size and total strain level on the magnitude of anelastic strain in granular freshwater ice. Cyclic loading...
Microstructure and Mechanical Behaviour of Ice
Short descriptions are given for ice in nature, test methods used to evaluate their deformation behaviour and, a general microstructure-based constitutive equation. Equations suitable...
Fractal Crushing
This paper develops an approach to a two-dimensional fragmentation process, in which floating ice floes are driven against each other and break up into smaller floes. It first considers...
Effect of Grain Size Variation on Damage in Polycrystalline Ice
This paper studies the effect of grain size distributions on damage accumulation in polycrystalline ice under uniaxial compression. The numerical results are derived from the internal-variable...
The Ductile-Brittle Transition in Ice & Size Effect
This paper considers the ductile to brittle transition in ice under compression. Two criteria, one phenomenological and the other more physical, are presented for the transition strain...
Preliminary Results of Direct Tension Tests on First-Year Sea Ice Samples
We present the initial results of our tests to determine the tensile behavior of columnar sea ice over a range of temperatures extending from -20 to -3?C and strain rates of 10-5...
Fracture Resistance to Cracking in Ice: Initiation and Growth
The issue of notch sensitivity and brittleness of the test failure is used to forecast the necessary specimen size for a material property initiation toughness; a methodology is developed...
Size Effects in the Fracture of Quasi-Brittle Materials
Causes and influences of the structural size effect that is exhibited by materials such as concrete, mortar, ice rock and ceramics, are discussed. The size effect law, which models this...
Laboratory Observations of Macroscopic Failure Modes in Freshwater Ice
A review is presented of tests performed in the laboratory by several investigators on indentation in freshwater ice. A number of the observed failure modes are discussed. From the results,...
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