TWO VARIANTS OF OUT-OF-LIMIT DEFORMATION OF SOLID AROUND WORKING

In the paper stress-strain behavior of solid around working in case of out-of-limit deformation when flat strain occurs is studied. Two limit variants are considered: when modulus of volumetric compression has much more value than modulus of decrease and vice a versa. In the first variant sizes of solid destruction zone are obtained, depending on limit strains of elasticity and strength of solid material. In the second variant solution at destruction zone differs from traditional elastic plastic solutions by maximal tangential stress increases with increasing of distance from working contour.

Analysis for Initiative Sub-Crack of Ellipse Fracture

By use of complex variable theory, formulae for tangential stress on ellipse edge are derived. Sub-crack point, opening angle and maximal tangential stress on ellipse edge are studied under uniaxial compression, biaxial compression, or uniaxial compression and crack water pressure separately. Based on the maximal tension stress criterion, formulas of maximal tangential stress and critical load are presented. The results show that sub-crack point, opening angle, maximal tangential stress and critical load are varied with different aspect ratio and different inclined angle. Meanwhile, the most dangerous inclined angle is obtained.