Torsion of laminated cylindrical shells with adhesive interlayers

Based on refined equations of the Timoshenko-type shell theory, the contact stresses in torsion of a two-layer cylindrical shell with an adhesive interlayer are numerically studied. The effect of the geometric and physical-mechanical parameters of the load-carrying layers and adhesive interlayer of the shell on the distribution of the interlaminar tangential stress is analyzed. The results are presented graphically.Presented at the 10th International Conference on the Mechanics of Composite Materials (Riga, April 20–23, 1998).Pidstryhach Institute of Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, Lviv, Ukraine. Translated from Mekhanika Kompozitnykh Materialov, Vol. 34, No. 4, pp. 501–506, July–August, 1998.     

Concerning the investigation of the supermolecular structure of polymers with a three-dimensional network

The results of an investigation of the structure and properties of a series of crosslinked polymers are presented. It is shown that the structure is determined by the chemical structure of the starting components and the method of synthesis.Institute of Chemistry of High-Molecular Compounds, Academy of Sciences of the Ukrainian SSR, Kiev. Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 5, pp. 934–936, September–October, 1970.     

Stress state of thermosensitive thick cylinders made of anisotropic composites

The class of problems on the axially symmetric stress state of thick cylinders made of anisotropic materials is considered. The problems are solved numerically. The temperature and mechanical fields in the composite cylinders are investigated taking into account the temperature dependence of the matrix and reinforcement characteristics, as well as the variability of density and angle of reinforcement across the thickness.Institute of Mechanics, Ukrainian National Academy of Sciences, Kiev, Ukraine. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 3, pp. 367–374, May–June, 1999.     

Effect of proton-electron irradiation on the strength of a glass-reinforced plastic and its components

The action of protons and electrons on the properties of glass strands under vacuum conditions has been experimentally investigated. The experimental procedure is described. The effects of irradiation, strain rate, and reduced temperature and pressure on the properties of glass reinforcement and glass-reinforced plastics are estimated.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev; Physicotechnical Institute of Low Temperatures, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 4, pp. 755–760, July–August, 1970.     

Resolvents of the theory of orthotropic shells with low shear stiffness in force-moments and stress functions

The problem of the theory of orthotropic layered shells with low shear stiffness is reformulated in force-moments and stress functions on the basis of new strain continuity relations constructed with allowance for transverse shears.Physicomechanical Institute, Academy of Sciences of the Ukrainian SSR, L'vov. Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 5, pp. 950–952, September–October, 1970.     

Effect of material properties on the stability of transversely isotropic shells with an elastic filler subjected to the action of mechanical loads and temperature

The effect of the low shear strength of the material (glass-reinforced plastic) on the stability of cylindrical shells with an elastic filler is investigated in relation to axial compression, external pressure, and heating. The equations of the thermoelastic problem of the theory of monotropic shells, constructed with allowance for the effect of tangential shearing stresses, are used in the calculations.Physicomechanical Institute, Academy of Sciences of the Ukrainian SSR, L'vov. L'vov Polytechnic Institute. Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 5, pp. 903–907, September–October, 1970.     

Waer of composite thin-walled structural elements with consideration of thermal effects

The contact problem on interaction of rigid stamps with anisotropic plates with regard to wear and the corresponding frictional heating is considered. The procedure developed is based on the reduction of the governing equation to a system of Volterra integral equations of the second kind. The numerical analysis allows us to study the effects of both the anisotropic thermoelastic characteristics of materials and the nature of the interaction of the contact-pair elements on the wear process.Pidstryhach Institute of Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, Lviv, Ukraine. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 3, pp. 309–318, May–June, 1999.     

Invariant semilinear elliptic equations on manifolds of constant negative curvature

Institute for Applied Problems of Mechanics and Mathematics, Ukrainian Academy of Sciences. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 26, No. 3, pp. 82–84, July–September, 1992.     

Uniqueness of solution in the nonlinear theory of dynamic viscoelasticity

The assertion of uniqueness of solution in the dynamic theory of physically nonlinear viscoelasticity is proved.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 6, pp. 1120–1122, November–December, 1971.     

On the applicability of two-dimensional applied theories to problems of the stability of axially loaded cylindrical shells made of materials with low shear stiffness

The applicability of two-dimensional applied theories of the Kirchhoff-Love, Timoshenko, and Ambartsumyan types to problems of the stability of shells with low shear stiffness [1] is discussed. The critical loads given by these theories are compared with those recently obtained [6–8] by solving the problem of the stability of a cylindrical shell on the basis of general solutions [3, 4] of the three-dimensional linearized equations of the theory of elasticity [5].Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. L'vov Polytechnic Institute. Translated from Mekhanika Polimerov, No. 1, pp. 141–143, January–February, 1970.     

Effect of ultrasound on the properties of a glass-reinforced plastic

It is shown that removing paraffin size from the glass strands by means of ultrasound has little effect on their strength, improves the structure of the material, and raises the mechanical strength of the GRP by 11–12%. An ultrasonic strand cleaner employing focusing piezoelectric ceramic transducers is described.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 3, pp. 546–548, May–June, 1969.     

Statistical theory of elasticity of reinforced plastics

A method of solving statistical boundary value problems in the stresses is proposed for microinhomogeneous composite media simulating the structure and properties of reinforced plastics. The coefficients of variation of the physical properties of the medium are not assumed small. Numerical examples are presented.Mekhanika Polimerov, Vol. 4, No. 3, pp. 438–444, 1968Presented on 5 June 1967 at a scientific seminar held at the Institute of Polymer Mechanics of the Academy of Sciences of the Latvian SSR.     

Effect of material structure on the stability of a laminated-plastic cylindrical shell

A compact equation is proposed for analyzing the stability of layered shells in relation to their structure. The case of a shell with split longitudinal-transverse winding subjected to hydrostatic pressure is investigated.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 1, pp. 147–150, January–February, 1971.     

Region of applicability of applied theories in problems of the stability of bars and plates with low shear stiffness subjected to uniaxial compression

The question of the region of applicability of applied theories of bending of bars and plates in stability problems is discussed in relation to the case of uniaxial compression. The critical loads given by these theories are compared with the recently obtained solution [4, 5, 7–10] based on the three-dimensional linearized equations of the theory of elasticity [6]. It is established that for the problems in question the Timoshenko and Ambartsumyan theories are accurate enough for engineering purposes over the entire practical region of variation of the geometric and physical parameters of the bar (plate), whereas the use of the Euler-Bernoulli and Kirchhoff-Love theories may lead to unacceptable errors.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev; Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga; Lvov Polytechnic Institute. Translated from Mekhanika Polimerov, No. 6, pp. 1124–1126, November–December, 1969.     

Solution of the second boundary value problem for one variant of the nonclassical theory of elasticity

The existence and uniqueness of the solution of the second boundary value problem of the nonclassical theory of elasticity describing the behavior of media with memory are investigated.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 1, pp. 88–91, January–February, 1971.     

Glass-reinforced plastic high-pressure tanks

The design and fabrication of lens-shaped tanks are described. The results of an investigation of the deformation and strength of the tanks are presented together with the data of cyclic tests.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 1, pp. 149–152, January–February, 1970.     

Stability of composite shells with an elastic core

The stability in axial compression of orthotropic cylindrical shells with an elastic core is investigated with allowance for the following factors: transverse shear strains in the shell material, precritical state of stress of the core, and the moments due to the surface forces exerted on the shell by the core. The numerical results obtained are compared with the results of approximate methods in which the above-mentioned factors are disregarded.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 3, pp. 544–547, May–June, 1976.     

Effect of deformation on the supermolecular structure of PN-1 copolymer

It is shown that under the combined influence of temperature and tensile stresses the spherical structure of crosslinked PN-1 copolymer becomes ellipsoidal. The change of shape is associated with the zone of high-elastic deformation.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 6, pp. 1129–1131, November–December, 1969.     

Accumulation of defects during nonstationary loading of Plexiglass

The fatigue resistance is studied in programmed tests on Plexiglass samples. The effect of the nonstationary character of loading and, in partcular, that of the shape of the load spectrum on durability of Plexiglass is estimated.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Mekhanika Polimerov, No. 1, pp. 169–171, January–February, 1972.     

Stability of a sandwich plate composed of rubbery material

The stability of a sandwich plate is investigated within the framework of the plane problem of the stability of nonlinear elastic incompressible bodies for finite subcritical strains and an arbitrary form of the potential. Numerical examples are considered for rubbery bodies with Treloar (neo-Hookean body) and Mooney potentials.Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Kiev Institute of the National Economy. Translated from Mekhanika Polimerov, No. 2, pp. 334–337, March–April, 1971.