Strength of honeycomb plastics in a flat stressed state

The strength of textile and paper honeycomb plastics in the flat stressed state is discussed, under the simultaneous action of compressing and shearing stresses. The application of a generalized strength criterion for anisotropic materials to honeycomb plastics is investigated.V. A. Kucherenko Central Scientific-Research Institute of Building Constructions, Moscow. Translated from Mekhanika Polimerov, No. 5, pp. 936–938, September–October, 1972.     

Long-term strength of rigid polyvinyl chloride in the flat stressed state

On the basis of experimental studies it has been established that the time to failure of rigid polyvinyl chloride depends basically on the magnitude of the largest stretching stress and at a long duration of testing deviates considerably from the exponential dependence. A refined formula is suggested for calculating the time to failure, which takes into account some characteristics of the stressed state.A. A. Zhdanov Leningrad State University. Translated from Mekhanika Polimerov, No. 3, pp. 453–457, May–June, 1970.     

The stress state of a plastic layer with a variable yield strength under a flat deformation

We study the stress state of a plastic layer with a variable yield strength in a strip under a flat deformation with a tensile load. We approximately calculate the first integrals of the system of plastic equilibrium equations, obtain an analog of the first Hencky theorem, and solve the conjugation problem for stresses on the contact boundary.     

On the influence of the viscoelastic properties of a material on the stressed state of a cylinder under diffusion saturation

We study the influence of relaxation effects on the stress-strain state of a cylinder when it is being diffusion saturated. The study is conducted for solid circular cylinders whose viscoelastic properties are described by various rheological models (those of Maxwell, Foigt, Lesersich, and Koltunov). We carry out an analysis of the stresses and give a comparison of the results for the materials under consideration.Translated fromMatematicheskie Melody i Fiziko-Mekhanicheskie Polya, Issue 31, 1990, pp. 41–44.     

The stressed state and certain fracture characteristics of glass-reinforced plastics loaded in tension at an angle to the direction of reinforcement

The stressed state of glass-reinforced plastic specimens with various structures is investigated experimentally in the case of tensile loads acting at 45° to the direction of reinforcement. A relation is established between the stress distribution over the cross section and the scale factor associated with the relative width of the understressed zones along the edges of the specimen. The fracture characteristics of GRP specimens with different structures are analyzed. Recommendations are given for testing GRP with different structures in tension at an angle of 45° to the direction of reinforcement.Mekhanika Polimerov, Vol. 3, No. 6, pp. 1030–1034, 1967     

The stressed state in a plate caused by the distortion tensor

The improved plate theory, which makes it possible to determine all the components of the stress tensor, is generalized to the case when the stressed state of a plate is caused by the distortion tensor. The equations obtained can be useful in the study of residual stresses in thinwalled elements, in applications of the method of distortion in the mechanics of failure and elsewhere.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 35, 1992, pp. 53–57.     

Strength of polyethylene and capron as a function of stretch ratio

The relation between the strengths and stretch ratios of a capronmonofilament and a high-pressure polyethylene film has been investigated for various stretching temperatures and stretching rates. The strength, measured at –196°C (_–196), is directly proportional to the stretch ratio (). For a given , _-196 does not depend on stretching temperature and stretching rate. The breaking load at –196° C (for a given initial cross section of the starting unoriented specimen) does not vary with . A possible explanation is offered.Mekhanika Polimerov, Vol. 3, No. 4, pp. 591–595, 1967     

Solution of the problem of the stressed state of a medium applied to the destruction of rock of nonuniform structure

We solve the two-dimensional problem of the distribution of stresses in a medium weakened by a system of cracks and elliptic holes loaded with a constant pressure. We obtain formulas that make it possible to determine the complex potentials of the two-dimensional problem of the theory of elasticity for the medium in question.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 27, 1988, pp. 103–106.     

Differences in the deformation and strength properties of human large blood vessels as a function of location,loading direction,and age

The separate and combined effect of various factors on the stress-elongation relation and the maximum stresses in human blood vessels has been studied on the basis of a statistical analysis of experimental data obtained in uniaxial and biaxial tension. Stress confidence intervals for vessels of the muscular and elastic types are determined. A correlation between maximum stress and age is established.     

On the stressed state in a fiber-reinforced composite material with twisted filaments

Using the model of a piecewise-homogeneous body in the framework of the linear theory of elasticity we study the distribution of internal stresses in a fiber-reinforced composite material with twisted filaments under loading at infinity by uniformly distributed normal strains in the direction of the filaments. It is assumed that the concentration of filaments is rather sparse and their interaction is not taken into account.Translated fromMatematicheskie Melody i Fiziko-Mekhanicheskie Polya, Issue 31, 1990, pp. 74–79.     

Symmetrization of the growth deformation and velocity gradients in residually stressed biomaterials

Some fundamental issues in the kinematic and kinetic analysis of the stress-modulated growth of residually stressed biological materials are addressed within the context of the multiplicative decomposition of deformation gradient into its elastic and growth parts. The symmetrizations of the growth part of the deformation gradient and the growth part of the velocity gradient are derived for isotropic pseudoelastic soft tissues. The significance of results in the formulation of the biomechanic constitutive theory is discussed.