关键词: nonholonomic dynamics, skating, scleronomic motion

Abstract: The conditions for fracture of anisotropic bodies and their geometry in stress space are proposed in this paper.The analytical formulae expressing the fracture conditions are es-tablished front the viewpoint of energy theory for crack propagation.In stress space the limiting surface corresponding to the fracture conditions derived for anisotropic solids is quadratic. It is an ellipsoid in case the mean stress is greater than zero and it is hyperboloid in case the mean stress is smaller than zero.The conclusions formed by the author in the present paper have certain generality. Some results obtained by predecessors appear to be special cases with respect to the present theory.

Key words: nonholonomic dynamics, skating, scleronomic motion