caa a22 4500 475840038 CHVBK 20180406123859.0 cr unu---uuuuu 170329e20000201xx s 000 0 eng 10.1023/A:1004738429373 doi (NATIONALLICENCE)springer-10.1023/A:1004738429373 Orthotropic viscous response of polar ice [Elektronische Daten] [R. Staroszczyk, L. Morland] Re-orientation of individual crystal glide planes as isotropic surface ice is deformed during its passage to depth in an ice sheet creates a fabric and associated anisotropy. A simple macroscopic description is that these material glide planes are rotated towards planes normal to an axis of compression, and away from planes normal to an axis of extension, inducing an instantaneous orthotropic viscous response with reflexional symmetries in the planes orthogonal to the current principal stretch axes. An associated orthotropic viscous law expresses the stress in terms of the strain-rate, strain, and three structure tensors based on the principal stretch axes. The fabric induced during differential stretchings along fixed principal axes, and the subsequent instantaneous viscous shear response in different planes due to the frozen fabric when the axial stress and strain-rate are removed, define a set of instantaneous directional viscosities in terms of the frozen principal stretches and the material response coefficients. Various inequalities and equalities between these viscosities are derived from the original rotation concepts, which, together with observed enhancement factors at large stretch and shearing, impose restrictions on the permitted response coefficients. It is shown how a simple viscous law can meet all these requirements, and such a law is illustrated for continued axial stretchings and shearing. Kluwer Academic Publishers, 2000 polar ice nationallicence induced anisotropy nationallicence orthotropy nationallicence Staroszczyk R. School of Mathematics, University of East Anglia, NR4 7TJ, Norwich, U.K. aut Morland L. School of Mathematics, University of East Anglia, NR4 7TJ, Norwich, U.K. aut Journal of Engineering Mathematics Kluwer Academic Publishers 37/1-3(2000-02-01), 191-209 0022-0833 37:1-3<191 2000 37 10665 https://doi.org/10.1023/A:1004738429373 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1004738429373 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Staroszczyk R. School of Mathematics, University of East Anglia, NR4 7TJ, Norwich, U.K aut NATIONALLICENCE 700 1- Morland L. School of Mathematics, University of East Anglia, NR4 7TJ, Norwich, U.K aut NATIONALLICENCE 773 0- Journal of Engineering Mathematics Kluwer Academic Publishers 37/1-3(2000-02-01), 191-209 0022-0833 37:1-3<191 2000 37 10665 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer