AEM Mechanics Research SeminarTuesday 24-Mar-2026, 12:20pm Central
Mr. Arnav GuptaTheoretical and Applied Mechanics, Cornell University
Title: Brittle fracture using the inverse-deformation approach Abstract: Many industrial and biological materials function under large deformations. A central
obstacle in modeling their fracture is the presence of cracks as
discontinuities in the deformation map. We overcome this issue by
solving for the inverse-deformation that maps points on the deformed
body to the reference domain. This map is continuous and is amenable to
analysis and reliable computations even in the presence of cracks. We
propose a non-convex energy density that asymptotes to a constant as the
local volumetric change approaches infinity. In the inverse-deformation
formulation, this energy appears as a two-well potential. A
higher-gradient term is incorporated that introduces a surface energy in
the model. The method predicts spontaneous nucleation and propagation
of cracks without using damage/phase variables or pre-existing flaws. We
derive an irreversibility condition for quasistatic motions of a
one-dimensional bar using the second law of thermodynamics. We prove
conditions for local stability that incorporate these restrictions.
Their numerical implementation shows that all broken equilibria of the
elastic bar are locally stable. For two-dimensional solids, we present
numerical results obtained using FEM-based bifurcation/continuation
methods. Fracture occurs at a critical load due to an elastic
instability. On further stretching, the cracks open and propagate at
their tips. The crack faces are sharp that
precisely delineate the solid material from empty space.For more information, visit the AEM Mechanics Research Seminar website: