STABILITY OF DEFORMATION AND A METHOD FOR THE CALCULATION OF THE FAILURE LOAD OF A FRAMED STRUCTURE REALIZING THE BIAXIAL TENSION OF AN ELEMENTARY CUBE
Stability of the biaxial tension of an elementary cube problem is considered. Material properties of this cube are described by the potential. The potential possesses convexity and concavity. A monotone incremental strain is applied through two linear elastic bars. Bifurcation sets and a separatrix for this gradient mechanical system are obtained. The loss-of-stability moment of the deformation process is determined. A numerical method that permits to construct the separatrix approximately without a nonlinear equilibrium equation is presented.