The paper deals with the minimum compliance problem of spatial structures made of
a nonhomogeneous elastic material of cubic symmetry. The elastic moduli as
well as the trajectories of anisotropy directions are design variables. The
isoperimetric condition fixes the value of the cost of the design expressed as
the integral of the unit cost assumed as a linear combination of the three
elastic moduli of the cubic symmetry. The problem has been reduced to the
pair of mutually dual auxiliary problems similar to those known from the
theory of materials with locking and from the transshipping theory. The
auxiliary minimization problem has the integrand of linear growth, which
transforms the problem considered to the topology optimization problem in which
simultaneously the shape of the structure and its material characteristics are
constructed. In contrast to the free material design which in the single load case
leads to the optimal Hooke tensor with a single nonzero eigenvalue, the
optimal Hooke tensor of cubic symmetry has either three or four nonzero
eigenvalues.
Keywords
free material design, cubic symmetry, topology optimization
Department of Structural Mechanics
and Computer Aided Engineering
Faculty of Civil Engineering
Warsaw University of Technology
ul. Armii Ludowej 16
00-637 Warsaw
Poland
Department of Structural Mechanics
and Computer Aided Engineering
Faculty of Civil Engineering
Warsaw University of Technology
ul. Armii Ludowej 16
00-637 Warsaw
Poland