We demonstrate the complexity that can exist in
the modelling of auxetic lattices. By introducing
pin-jointed members and large deformations to the
analysis of a re-entrant structure, we create a material
which has both auxetic and non-auxetic phases. Such
lattices exhibit complex equilibrium behaviour during
the highly nonlinear ...
We demonstrate the complexity that can exist in
the modelling of auxetic lattices. By introducing
pin-jointed members and large deformations to the
analysis of a re-entrant structure, we create a material
which has both auxetic and non-auxetic phases. Such
lattices exhibit complex equilibrium behaviour during
the highly nonlinear transition between these two
states. The local response is seen to switch many times
between stable and unstable states, exhibiting both
positive and negative stiffnesses. However, there is
shown to exist an underlying emergent modulus over
the transitional phase, to describe the average axial
stiffness of a system comprising a large number of
cells.
