TO INVESTIGATE CALCULATION OF PARAMETRIC VIBRATIONS OF VISO BAR IN MEDIUM WITH REGARD TO DAMAGEABILITY

Pirmamedov I.T., the Institute of Mathematics and Mechanics of NAS of Azerbaijan, Baku

In the paper on the basis of the theory of damageability consider parametric vibrations of a linear inhomogeneous in thickness bar with regard do physical and geometrical non-linearity, buried in viso medium. The problem is solbed by variational method. Characteristic curbes of dependend of applied force on frequency are constructed.

parametric vibrations, thickness bar, frequency

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THE BENDING OF THREE-LAYER ELASTIC CORE WITH VARIABLE STIFF SHELL

Pleskachevsky Yu.M., The A.V. Luikov Heat and Mass Transfer Institute of NAS of Belarus, Minsk, the Republik of Belarus

Starovoytova E.E., the Belarusian State University of Transport, Gomel, the Republik of Belarus

The bending of three-layer elastic core with variable thickness of one of two stiff shells is considered. To describe kinematics of asymmetrical over thickness pack of the core the hypotheses of the broken normal are accepted. A system of equilibrium equations and its general analytical solution in terms of displacements haves been derived.

three-layer elastic core, asymmetrical over thickness pack

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MOLECULAR-STATISTICAL THEORY OF ELASTIC AND VISCOUS PROPERTIES OF RUBBER-LIKE MATERIALS WITH ORIENTATIONAL ORDER

Nemtsov V.B., Belarusian State Technological University, Minsk, the Republik of Belarus

Kamluk A.N., Belarusian State Technological University, Minsk, the Republik of Belarus

Shirko A.V., Belarusian State Technological University, Minsk, the Republik of Belarus

The paper contains the results of investigation of elastic and viscous properties of rubber-like materials with orientational order. The elastic properties are described with the help of the introduced microscopic Cauchy-Green tensor. The obtained results describe the nonlinear elastic properties well and predict the existence of the soft modes. In the theory of viscous properties the approved model for the time correlation function of the microscopic stress tensor is used.

elastic properties, rubber-like materials, time correlation function

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ON BIFURCATION OF THIN CORRUGATED SHELL WITH AN ELASTIC FILLER UNDER ACTION OF NON-UNIFORM HYDROSTATIC PRESSURE

Nikonova T.V., the Vitebsk State Technological University, Vitebsk, the Republik of Belarus

Kuntsevich S.P., the Vitebsk State Technological University, Vitebsk, the Republik of Belarus

Mikhasev G.I., the Belarusian State University, Minsk, the Republik of Belarus

The problem of buckling of a thin corrugated shell with elastic filler under action of the non-uniform hydrostatic pressure is considered. The influence of the elastic filler is taken into account as the additional pressure within the framework of Winkler's model. The semi-moment equations of the thin elastic shell theory are assumed as the governing ones. The rigid clamped conditions are considered at the edges of the shell. Assuming that the hydrostatic pressure depends upon the circumferential co-ordinate, solutions of the governing equations are constructed in the form of functions decaying far from some generator on the shell surface. Using the complex WKB-method, the boundary-value problem is reduced to the sequence of the one-dimensional boundary-value problems. The equation for the critical normal pressure has been obtained. The influence of parameters of corrugation of the shell on the critical pressure has been analyzed.

buckling, thin corrugated shell, hydrostatic pressure, elastic filler, complex WKB-method

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