The
paper discusses the problem of designing the stiffest frame with a given and
fixed number of joints and element
connections. The design variables are the
radii of the circular cross sections of the bars or/and the nodal points
locations. In each case a maximal volume of a frame, constituting an
isoperimetric unilateral condition is prescribed. The nodal force vector is
assumed to be independent of the design variables, hence fixed during the
optimization process. New optimal
layouts of space frames are presented. These
new layouts are found by using the moving asymptotes algorithm. Symbolic capabilities
of the Maple system to obtain exact analytical formulae for the gradient of the
frame compliance were applied in the sensitivity analysis of the structure,
translated into C programming language and used in the optimization program
written in the C++ language.