On elastic response of disordered triangular lattice during dynamic loading

The present investigation focuses on an observation regarding the initial elastic response of a triangular geometrically and structurally disordered lattice during medium-to-high strain rate loading. Namely: a transition from the short-time modulus of elasticity to the long-time one, which is not accompanied by the corresponding change of the stiffness tensor. It is demonstrated that the difference between the two moduli is, in the case of the homogeneous biaxial test simulations performed herein, a consequence of the geometrical and structural disorder "quenched" within the lattice. The investigation is performed on the triangular lattice with the first-neighbor central interactions under practically identical in-plane conditions over eight decades of strain rate