Evaluation of the criticality of cracks in ice shelves using finite element simulations

Abstract

Abstract. The ongoing disintegration of large ice shelf parts in Antarctica raise the need for a better understanding of the physical processes that trigger critical crack growth in ice shelves. Finite elements in combination with configurational forces facilitate the analysis of single surface fractures in ice under various boundary conditions and material parameters. The principles of linear elastic fracture mechanics are applied to show the strong influence of different depth dependent functions for the density and the Young's modulus on the stress intensity factor K I at the crack tip. Ice, for this purpose, is treated as an elastically compressible solid and the consequences of this choice in comparison to the predominant incompressible approaches are discussed. The computed stress intensity factors K I for dry and water filled cracks are compared to critical values K Ic from measurements that can be found in literature.

A Generalized Interpolation Material Point Method for Shallow Ice Shelves. 2: Anisotropic Nonlocal Damage Mechanics and Rift Propagation

“…In the literature, analytical LEFM models were applied to estimate the penetration depth of crevasses (Weertman, 1973;Smith, 1976;Rist et al, 2002;van der Veen, 1998a,b) and to study rift propagation in ice shelves (Hulbe et al, 2010;Plate et al, 2012;Larour et al, 2004a,b;Lipovsky, 2018Lipovsky, , 2020. Moreover, analytical LEFM models were combined with ice flow models to predict iceberg calving (Krug et al, 2014;Yu et al, 2017) and to investigate ice shelf stability (Lai et al, 2020).…”

“…Crevasse/rift propagation in LEFM models is based on the stress intensity factor and fracture toughness of ice, which are inherently related to strain energy release rate (where rate indicates per unit crack length) and fracture energy (i.e., the surface energy associated with the crack face), respectively. In the literature, analytical LEFM models were applied to estimate the penetration depth of crevasses (Rist et al., 2002 ; Smith, 1976 ; van der Veen, 1998a , 1998b ; Weertman, 1973 ) and to study rift propagation in ice shelves (Hulbe et al., 2010 ; Larour et al., 2004a , 2004b ; Lipovsky, 2018 , 2020 ; Plate et al., 2012 ). Moreover, analytical LEFM models were combined with ice flow models to predict iceberg calving (Krug et al., 2014 ; Yu et al., 2017 ) and to investigate ice shelf stability (Lai et al., 2020 ).…”

A generalized interpolation material point method for shallow ice shelves. Part II: anisotropic nonlocal damage mechanics and rift propagation

“…In the literature, analytical LEFM models were applied to estimate the penetration depth of crevasses (Weertman, 1973;Smith, 1976;Rist et al, 2002;van der Veen, 1998a,b) and to study rift propagation in ice shelves (Hulbe et al, 2010;Plate et al, 2012;Larour et al, 2004a,b;Lipovsky, 2018Lipovsky, , 2020. Moreover, analytical LEFM models were combined with ice flow models to predict iceberg calving (Krug et al, 2014;Yu et al, 2017) and to investigate ice shelf stability (Lai et al, 2020).…”

Modeling hydraulic fracture of glaciers using continuum damage mechanics

“…It is also possible to attempt to predict the penetration depth (height) of surface (basal) crevasses using various formulations of fracture mechanics (Weertman, 1980; Van der Veen, 1998a, b; Benn and others, 2007; Plate and others, 2012). Alternatively, the Nye zero-stress model (Nye, 1957; Jezek, 1984; Nick and others, 2010) may be used to predict crevasse penetration depths based on the assumption that a crevasse penetrates to the point where horizontal stress vanishes.…”