Author(s): R. L. Brown; J. A. Richter-Menge; G. F. N. Cox
Linked Author(s):
Keywords: No Keywords
Abstract: Two constitutive formulations are used to represent the constitutive behavior of columnar sea ice under variable path compressive loadings. The first is a single integral representation which has been successfully used to model viscoelastic materials. This representation is a convenient form for describing nonlinear rate-dependent properties and is mathematically more tractable than multiple integral representations or nonlinear differential relations. The second constitutive formulation is an elastic-viscoplastic relation which defines the instantaneous strain rate in terms of several microdynamical variables (compressive mobile dislocation density, tensile mobile dislocation density, and specific microcrack surface area). The two constitutive theories were adjusted to experimental data for compressive strain rate tests. For constant strain rates, both formulations appeared to work well. For variable deformation rates, the second formulation demonstrated superior representation of the material response.
Year: 1986