[PDF] Sea Ice Behaviour In Creep Fracture Regime eBook

Author : Caizhao Zhan
Publisher :
Page : 578 pages
File Size : 39,63 MB
Release : 1993
Category : Ice mechanics
ISBN :

GET BOOK

In the last part, Sinha's creep model was generalized into 3-D and implemented into a finite element program. (Abstract shortened by UMI.).

Author : Erland M. Schulson
Publisher : Cambridge University Press
Page : 403 pages
File Size : 31,45 MB
Release : 2009-04-30
Category : Science
ISBN : 0521806208

GET BOOK

The first complete account of the physics of the creep and fracture of ice, for graduates, engineers and scientists.

Author : Malcolm Mellor
Publisher :
Page : 120 pages
File Size : 35,43 MB
Release : 1983
Category : Elastic properties
ISBN :

GET BOOK

The first part of the report provides an introduction to the mechanics of deformable solids, covering the basic ideas of stress and strain, rheology, equilibrium equations, strain/displacement relations, constitutive equations, and failure criteria. Fracture mechanics and fracture toughness are also reviewed briefly. The second part summarizes available data on the mechanical properties of freshwater ice and saline ice, accounting for the influences of strain rate and loading rate, temperature, porosity, salinity, and grain size. Boundary value problems are not dealt with, but there is discussion of some miscellaneous topics, including thermal strains, behavior of brash ice, and pressure ridges. The report was written as a study text for a NATO Advanced Study Institute on Sea/Ice/Air Interactions, and was intended to be used in conjunction with companion texts on related topics. This report was written during the summer of 1981, and thus does not cover all results which appeared after the end of 1981.

Author : Jerome Weiss
Publisher : Springer Science & Business Media
Page : 95 pages
File Size : 42,2 MB
Release : 2013-03-14
Category : Science
ISBN : 940076202X

GET BOOK

Sea ice is a major component of polar environments, especially in the Arctic where it covers the entire Arctic Ocean throughout most of the year. However, in the context of climate change, the Arctic sea ice cover has been declining significantly over the last decades, either in terms of its concentration or thickness. The sea ice cover evolution and climate change are strongly coupled through the albedo positive feedback, thus possibly explaining the Arctic amplification of climate warming. In addition to thermodynamics, sea ice kinematics (drift, deformation) appears as an essential factor in the evolution of the ice cover through a reduction of the average ice age (and consequently of the cover's thickness), or ice export out of the Arctic. This is a first motivation for a better understanding of the kinematical and mechanical processes of sea ice. A more upstream, theoretical motivation is a better understanding of the brittle deformation of geophysical objects across a wide range of scales. Indeed, owing to its very strong kinematics, compared e.g. to the Earth’s crust, an unrivaled kinematical data set is available for sea ice from in situ (e.g. drifting buoys) or satellite observations. Here, we review the recent advances in the understanding of sea ice drift, deformation and fracturing obtained from these data. We focus particularly on the scaling properties in time and scale that characterize these processes, and we emphasize the analogies that can be drawn from the deformation of the Earth’s crust. These scaling properties, which are the signature of long-range elastic interactions within the cover, constrain future developments in the modeling of sea ice mechanics. We also show that kinematical and rheological variables such as average velocity, average strain-rate or strength have significantly changed over the last decades, accompanying and actually accelerating the Arctic sea ice decline.

Author :
Publisher :
Page : 12 pages
File Size : 26,84 MB
Release : 1996
Category :
ISBN :

GET BOOK

This final report summarizes research on deformation and fracture models for sea ice. In many cases results are compared with those for freshwater ice. Described first is work on modeling of primary creep for relatively short loading histories, studies on the applicability of linear elastic fracture mechanics to polycrystalline freshwater and sea ice, and finally a study on stress-transmission in polycrystals undergoing grain boundary sliding. Next, emphasis is on characterization of time-dependent deformation behavior of ice from short to very long-time behavior. This behavior requires the use of models that account for broad spectrum viscoelasticity. Linear viscoelasticity theory is used first in order to develop an understanding of how single-crystal creep produces broad-spectrum behavior of polycrystals through the mechanical interaction of single crystals. Guided by these results and then nonequilibrium thermodynamic principles, nonlinear viscoelastic constitutive equations are developed that make direct use of creep compliances predicted from the linear theory of polycrystals. While only theoretical work has been done on this grant, experimental data provided by others have been used to verify some of the predictions. Comparison of theory and experiment appears in some of the publications.

Author : Wilford Frank Weeks
Publisher :
Page : 92 pages
File Size : 13,22 MB
Release : 1969
Category : Fracture mechanics
ISBN :

GET BOOK

The increased activity in cold regions has made a thorough understanding of fracture in lake and sea ice quite desirable, inasmuch as this information has application to a number of problems of geophysical as well as engineering importance. This survey starts with a discussion of the structure of ice I and the macro- and microstructure of sea and lake ice as well as their chemistry and phase relations. Recent work on the direct observation of dislocations as well as the formation of cracks in ice is summarized. Formal ice-brine-air models for analyzing variations in ice strength are also reviewed. The results of the different types of tests are discussed and compared (compressive, indentation, direct and ring-tension, small beam flexure and in situ cantilevers and simple beams, shear, and impact). Scale effects are considered as well as the rapid strength deterioration experienced by ice sheets in the spring. Finally, a number of recommendations are made concerning future research in this field. (Author).

Author : E. M. Schulson
Publisher :
Page : 417 pages
File Size : 42,53 MB
Release : 2014-05-14
Category : Ice
ISBN : 9780511540752

GET BOOK

The first complete account of the physics of the creep and fracture of ice for graduates, engineers and scientists.

Author : Ryszard Staroszczyk
Publisher : Springer
Page : 334 pages
File Size : 36,73 MB
Release : 2018-12-29
Category : Science
ISBN : 3030030385

GET BOOK

This book presents the concepts and tools of ice mechanics, together with examples of their application in the fields of glaciology, climate research and civil engineering in cold regions. It starts with an account of the most important physical properties of sea and polar ice treated as an anisotropic polycrystalline material, and reviews relevant field observations and experimental measurements. The book focuses on theoretical descriptions of the material behaviour of ice in different stress, deformation and deformation-rate regimes on spatial scales ranging from single ice crystals, those typical in civil engineering applications, up to scales of thousands of kilometres, characteristic of large, grounded polar ice caps in Antarctica and Greenland. In addition, it offers a range of numerical formulations based on either discrete (finite-element, finite-difference and smoothed particle hydrodynamics) methods or asymptotic expansion methods, which have been used by geophysicists, theoretical glaciologists and civil engineers to simulate the behaviour of ice in a number of problems of importance to glaciology and civil engineering, and discusses the results of these simulations. The book is intended for scientists, engineers and graduate students interested in mathematical and numerical modelling of a wide variety of geophysical and civil engineering problems involving natural ice.