An inverse coefficient problem related to identification of the plasticity function g(η) from a given torque τ is studied for a circular section bar. Within the deformation theory of plasticity the mathematical model of torsion leads to the nonlinear Dirichlet problem −∇ · (g(|∇u|2)∇u) = 2φ, x ∈ Ω ⊂ R2; u(s) = 0, s ∈ ∂Ω . For determination of the unknown coefficient g(η) ∈ G, an integral of the...

To determine the degree to which the capillary blood vessels in vivo are supported by the elasticity of the surrounding tissue, a study was made of the elastic properties of the mesentery of the rabbit. A torsion test was made on a circular membrane of the avascular region of the mesentery, by applying a graded static torque and measuring the resulting deformation. The mesentery was found to ha...

We study three-dimensional deformations of thin inextensible elastic rods with nonvanishing spontaneous curvature and torsion. In addition to the usual description in terms of curvature and torsion which considers only the configuration of the centerline of the rod, we allow deformations that involve the rotation of the rod’s cross-section around its centerline. We derive new expressions for th...

Size effects are explored experimentally in a tetragonal lattice structure. Size dependence of rigidity is nonclassical elastic and is interpreted via Cosserat elasticity. The characteristic lengths are about a third the cell size. The Cosserat characteristic length for torsion is `t = 5.6 mm. The characteristic length for bending is `b = 5.4 mm. The size effect in torsion was a factor 4.5 in r...

This paper considers the explicit solutions of free-edge stresses near circumferential cracks in surface coatings of circular torsion bars and their application in determining the progressive cracking density in the coating layers. The problem was formulated within the framework of linear elastic fracture mechanics (LEFM). The free-edge stresses near crack tip and the shear stresses in the cros...