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Title: A Finite-Element-Based Cohesive Zone Model of Water-Filled Surface Crevasse Propagation in Floating Ice Tongues
We present a finite-element-based cohesive zone model for simulating the nonlinear fracture process driving the propagation of water-filled surface crevasses in floating ice tongues. The fracture process is captured using an interface element whose constitutive behavior is described by a bilinear cohesive law, and the bulk rheology of ice is described by a nonlinear elasto-viscoplastic model. The additional loading due to meltwater pressure within the crevasse is incorporated by combining the ideas of poromechanics and damage mechanics.We performed several numerical studies to explore the parametric sensitivity of surface crevasse depth to ice rheology, cohesive strength, density, and temperature for different levels of meltwater depth.We find that viscous (creep) strain accumulation promotes crevasse propagation and that surface crevasses propagate deeper in ice shelves/tongues if we consider depth-varying ice density and temperature profiles. Therefore, ice flow models must account for depth-varying density and temperature-dependent viscosity to appropriately describe calving outcomes.  more » « less
Award ID(s):
1847173
PAR ID:
10495676
Author(s) / Creator(s):
; ; ;
Editor(s):
Irina Tezaur, Josefin Ahlkrona
Publisher / Repository:
IEEE Computer Society
Date Published:
Journal Name:
Computing in Science & Engineering
Volume:
25
Issue:
3
ISSN:
1521-9615
Page Range / eLocation ID:
8 to 16
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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