A temperature dependent creep damage model for polycrystalline ice

Duddu, Ravindra; Waisman, Haim

doi:10.1016/j.mechmat.2011.11.007

Cited by 70 publications

(93 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These parameter values are within the range of previous studies (Duddu and Waisman, 2012;Lliboutry, 2002;Vaughan, 1993).…”

supporting

confidence: 89%

Calving relation for tidewater glaciers based on detailed stress field analysis

Mercenier¹,

Lüthi²,

Vieli³

2017

Preprint

View full text Add to dashboard Cite

Abstract. Ocean terminating glaciers in Arctic regions have undergone rapid dynamic changes in recent years, which have been related to a dramatic increase in calving rates. Iceberg calving is a dynamical process strongly influenced by the geometry at the terminus of tidewater glaciers. We investigate the effect of varying water level, calving front slope and basal sliding on the stress state and flow regime for an idealized grounded ocean-terminating glacier and scale these results with ice thickness and velocity. Results show that water depth and calving front slope strongly affect the stress state while the effect from variations in 5 basal sliding is much smaller. An increased relative water level or a reclining calving front slope strongly decrease the stresses and velocities in the vicinity of the terminus and hence have a stabilizing effect on the calving front. We find that surface stress magnitude and distribution are determined by solely the water depth relative to ice thickness for simple geometries. Based on this scaled relationship for the stress peak at the surface, and assuming a critical stress for damage initiation, we propose a simple and new parametrization for calving rates for grounded tidewater glaciers that is in good agreement with observations.

show abstract

“…These parameter values are within the range of previous studies (Duddu and Waisman, 2012;Lliboutry, 2002;Vaughan, 1993).…”

supporting

confidence: 89%

Calving relation for tidewater glaciers based on detailed stress field analysis

Mercenier¹,

Lüthi²,

Vieli³

2017

Preprint

View full text Add to dashboard Cite

show abstract

“…The strain-ratedependent nature of the transition from ductile to brittle implies that -depending on the viscosity -fracture in ice occurs on timescales of less than a few seconds to hours, which DES easily resolves. Appendix A presents the weakening parameters used to calibrate semi-brittle ice in DES against laboratory-derived strain-and strain-rate-vs.-time curves, as well as listing all relevant material and numerical parameters that reproduce this behavior (following essentially the same exercise as in Duddu and Waisman, 2012). Most important, we recover the value of plastic strain that indicates when semi-brittle ice has ruptured.…”

Section: Semi-brittle Behaviormentioning

confidence: 99%

“…A1). We essentially followed the same exercise as in Duddu and Waisman (2012), in which material parameters are calibrated against deformation curves derived by Mahrenholtz and Wu (1992). While this exercise has its limitations (laboratory-grown ice does not necessarily represent natural ice), it is our attempt at reproducing ice behavior to the best of DES's ability.…”

Section: Appendix A: Semi-brittle Ice Calibrationmentioning

confidence: 99%

“…Thus, both the FS and SIA/SSA formulations often employ parametrizations for the most physically complicated aspects of their systems. In particular, the failure of ice within many ice sheet models is often treated using linear elastic fracture mechanics (e.g., Larour et al, 2004), as a rheologically more flexible, time-dependent scalar damage field (e.g., Duddu and Waisman, 2012), or a mixture of the two (Krug et al, 2014(Krug et al, , 2015.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Semi-brittle rheology and ice dynamics in DynEarthSol3D

et al. 2017

View full text Add to dashboard Cite

Abstract. We present a semi-brittle rheology and explore its potential for simulating glacier and ice sheet deformation using a numerical model, DynEarthSol3D (DES), in simple, idealized experiments. DES is a finite-element solver for the dynamic and quasi-static simulation of continuous media. The experiments within demonstrate the potential for DES to simulate ice failure and deformation in dynamic regions of glaciers, especially at quickly changing boundaries like glacier termini in contact with the ocean. We explore the effect that different rheological assumptions have on the pattern of flow and failure. We find that the use of a semibrittle constitutive law is a sufficient material condition to form the characteristic pattern of basal crevasse-aided pinchand-swell geometry, which is observed globally in floating portions of ice and can often aid in eroding the ice sheet margins in direct contact with oceans.

show abstract

“…However, it is important to note that crevasses are tensile cracks, so Galiardini and others' main criticism regarding the damage description under compression in Duddu and Waisman (2012) is not relevant to crevasse propagation, which is our main interest. The appropriateness of our model for investigating tensilestress-induced surface crevasse propagation in glaciers and ice sheets is demonstrated in our recent publication (Duddu and others, 2013).…”

Section: Introductionmentioning

confidence: 99%