Showing papers in "Cold Regions Science and Technology in 1990"

TL;DR: In this article, rates of frost shattering were determined for 47 different samples of saturated rocks partially immersed in water by a decreasing rate of the longitudinal wave velocity during freeze-thaw cycles.

TL;DR: In this paper, a model was developed for predicting the large-scale compressive strength of sea ice sheets using 283 small-scale strength tests and the relationships between the intrinsic and extrinsic properties of the ice sheet.

TL;DR: In this article, a dynamic simulation model of lake water temperature developed for summer conditions is extended to accomplish the year-round one-dimensional, unsteady simulation of hydrothermal processes in a lake located in the temperate region.

TL;DR: In this paper, the authors considered the mechanics of snow slab release from the viewpoint of mechanics of continua and showed that snow cannot fracture until a critical strain rate and a critical fracture strain is reached in a weak layer of the snowpack.

TL;DR: In this paper, the authors present the results of a field study which was carried out at a site near the EHV transmission facilities of Ontario Hydro most severely impacted by the March 10, 1986 storm.

TL;DR: In this article, a theoretical analysis of crack nucleation in isotropic polycrystalline ice due to the elastic anisotropy of the constituent crystals is presented, where the singularity of the associated stress concentrations near a grain-boundary facet junction provides the mechanism for inducing micro-crack precursors, if similar nuclei do not already exist.

TL;DR: In this paper, the results of a series of reversed direct-stress experiments performed on freshwater ice are discussed in terms of the mechanisms underlying the behavior, with particular attention to dislocation processes.

TL;DR: In this article, the steady growth of a segregated ice layer in freezing soils is studied mathematically under three distinct and representative hypotheses on the properties of the frozen fringe, chosen among many such hypotheses reported in the literature.

TL;DR: In this article, a four-constituent model of a natural snowpack is presented, where the conservation equations are written in terms of partial variables whereas material constitutive laws are given in terms with intrinsic variables.

TL;DR: In this article, the authors examined the theoretical generality of constitutive models for the transient creep of polycrystalline ice and the ability of such models to represent knowledge derived from experimentation in a physically consistent manner.

TL;DR: In this paper, the authors determined the coefficient of sensible heat transfer between water and ice at a depth of 1 m and an estimated surface roughness of about 0.01 m. This value is within the limits of smooth and rough ice conditions found in laboratory investigations and appears to be somewhat less than that found in recent sea ice studies.

TL;DR: In this article, an alternative experimental method was used in this study, which is easy to handle even with this prototype equipment, should be more accurate than the old method since one possible source of error (the external pressure) is eliminated.

TL;DR: In this paper, the unfrozen water content of a saturated clayey silt consolidated to two void ratios was determined using a differential scanning calorimeter, and the results supported the former view since the amount of nonfreezable water in the densest specimen was three times higher than that of the sample with the largest voids.

TL;DR: In this article, a time-independent incremental plasticity model was developed for normally-consolidated broken ice, where both the yield criterion and potential function were found to depend on the void ratio.

TL;DR: In this article, the authors describe the measurement techniques and procedures required to simulate a condition of freezing rain in the laboratory and presents related quantitative measurements which enable assessment of resulting holdover behaviour of de/anti-icing fluids.

TL;DR: In this paper, a series of freezing tests on three kinds of soil were conducted to find the steady growth condition of a segregated ice layer by using a new steady-state method in which the temperature profiles of soil specimens were controlled.

TL;DR: In this article, the drift motions of icebergs driven by waves and currents toward a large offshore structure are examined and results from a series of experiments with various iceberg sizes and environmental conditions are presented and compared with predictions of a corresponding numerical model.

TL;DR: In this article, a new experimental method was introduced to determine D2 of a soil with known empirical functions D1 and D2, and the D2 was determined as a function of w at several temperatures ranging between − 1.0 and 1.5°C.

TL;DR: In this article, the effects of positive and negative corona discharges on a tip of conical ice as a function of corona current, temperature and atmospheric conditions were investigated.

TL;DR: In this article, a fixture for performing completely reversed (i.e., tension to compression) uniaxial stress experiments on ice is described, which rigidly holds an ice specimen having bonded end caps without loading the specimen or inducing a bending moment.

TL;DR: In this article, four sites on a flat terrain with Tertiary sediments at Seymour Island were sounded for permafrost depths with VES: two on the Meseta at 200 m a.s.l. and one near the shore line at Larsen.

TL;DR: In this article, a model is developed which relates the ice-surface topography above subglacial lakes to the length l of bed transition regions bordering the lake where the effect of the presence of the lake causes a reduction in basal shear stress.

TL;DR: In this article, an attempt is made to formulate a nonlinear constitutive relation applicable to the prediction of creep loads on structures in deep snow covers, and the resulting formulation, although approximate, is the simplest model to model the flow of a granular material composed of ice grains in a realistic manner.

TL;DR: In this paper, the authors show the linkages between the thermodynamic and rheological properties of the ice sandwich, and the implications of the analysis with respect to the thermodynamics and the rheology of frozen soils are discussed.

TL;DR: A new underwater frazil ice detector developed at USACRREL is described in this article, which can automatically start de-icing procedures and alert operators to the presence of frazil.

TL;DR: In this paper, the expansion of a permafrost region into an aquifer due to surface cooling is investigated for purely vertical motion, and the expansion is treated as binary mixtures, separated by a moving interface.

TL;DR: In this article, the radon levels from an area of silty soils varied from 14 to 348 pCi 1 − 1 and averaged 51 pCI 1 −1 where the top of permafrost was within a meter of the ground surface.

TL;DR: In this paper, the authors devise strategies for optimum deployment of Tiros satellite-tracked Ocean Drifters (TOD) in order to derive measurements of ocean currents for iceberg drift forecasting off the Canadian east coast.

TL;DR: In this article, three new samplers were developed for detailed analysis of the three-dimensional characteristics of frazil ice deposits beneath an ice cover, which provided information on a deposit's internal structure, stratigraphy and sedimentology, geometry and physical properties.