Constitutive equations with pressure-dependent rheological parameters for describing ice creep

• Published in: Journal of Glaciology
• Main Authors: MARTINA ARCANGIOLI, ANGIOLO FARINA, LORENZO FUSI, GIUSEPPE SACCOMANDI
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2019
• Subjects: glacier flow; ice dynamics; ice rheology; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2019.31; https://doaj.org/article/c2d0d7265e664cce83a37dd66f426724

Experimental data from creep tests on polycrystalline ice samples highlight not only the non-Newtonian behavior of ice but also suggest a critical dependence of the various rheological parameters upon the applied hydrostatic pressure. We propose a new modeling framework, based on implicit theories of continuum mechanics, that generalizes two well-known constitutive models by taking into account the effect of the pressure in the description of ice in creep. To ascertain the validity of the proposed models, we fit the physical parameters with experimental data for the elongational flow of ice samples. The results show good agreement with the experimental creep curves. In particular, the proposed generalized models reproduce the increase of the creep rate due to the presence of hydrostatic pressure.