MICROPOLAR MEDIUM AS A MODEL FOR BUCKLING OF GRID FRAMEWORKS.

Attention is focused on large rectangular frameworks of constant mesh size and constant properties of members in each direction. The framework is considered to be under initial axial loads. A continuous approximation for the expression of potential energy is formulated and, postulating an equivalent micropolar continuum under initial stress, differential equations of equilibrium in terms of displacements and rotations are derived. Expressions for stresses, couple stresses and constitutive relations are also presented.