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The three-dimensional problem of stability of layered coatings at normal and high temperatures and small precritical strains is formulated and solved and the characteristic equations are derived. The temperature dependence of the physical and mechanical parameters of specific layered coatings is established experimentally. Three-layer coatings on a homogeneous substrate at different temperatures are considered as an example. Recommendations for establishing the optimal service conditions for layered structural members with coatings are formulated. [ABSTRACT FROM AUTHOR]

Results on stress concentration in thin shells with curvilinear holes subject to plastic deformation and finite deflections are reviewed. The holes (circular, elliptical) are reinforced with thin-walled elements (rings, rods) of different stiffness. A numerical method of solving doubly nonlinear problems of statics for shells of complex geometry is outlined. The stress distribution near curvilinear holes in spherical, cylindrical, and conical shells under statical loading is studied. The numerical results are analyzed [ABSTRACT FROM AUTHOR]

The paper outlines a method and results of experimental determination of vibratory stresses in a shell structure contacting with a medium. The stresses peak at the junction between the shell and the branch pipe. It is established that when the shell is in contact with the medium, the vibratory stresses are much higher, while the vibratory accelerations are much lower [ABSTRACT FROM AUTHOR]

A technique and results of experimental determination of vibrational stresses in a system of two truncated conical shells joined by three thin plates are presented. An analysis of the data obtained shows that the stress peaks near the added point mass at resonance [ABSTRACT FROM AUTHOR]

A mathematical model is proposed to describe the static deformation of a unidirectional fiber-reinforced composite under plane-strain conditions in a plane perpendicular to the fiber direction. The model is based on the stochastic static equations for an elastic homogeneous two-component medium with nonzero body forces. Applying the method of conditional moments and double Fourier transform yields a nonlocal model in the form of integro-differential equations. Expanding the integral kernels into series in expansion coefficients yields differential equations whose order depends on the number of terms in the series. The zero-order approximation leads to the theory of effective moduli, the first-order approximation to the refined theory of effective moduli, and the second-order approximation to fourth-order equilibrium equations for mean displacements (mathematical expectations) and formulas for displacements, strains, and stresses averaged over the composite and its components. All the coefficients in theses formulas are expressed in terms of the elastic constants of the components and the geometric parameters of the structure. The model is valid for heavy stress gradients. In a particular case, the static theory of two-component elastic mixtures follows from the model [ABSTRACT FROM AUTHOR]

The magnetoelastic stress-strain problem for a transversely isotropic ferromagnetic body with an elliptical crack in the isotropy plane is solved explicitly. The body is in an external magnetic field perpendicular to the isotropy plane. The magnetic field induces elastic strains and an internal magnetic field in the body. The main characteristics of stress-strain state and induced magnetic field are determined and their features in the neighborhood of the crack are analyzed. Formulas for the stress intensity factors of the mechanical and magnetic fields near the crack tip are presented [ABSTRACT FROM AUTHOR]

The magnetoelastic problem for a transversely isotropic ferromagnetic body with a parabolic crack in the plane of isotropy is solved explicitly. The body is in an external magnetic field, which is perpendicular to the plane of isotropy. The field induces elastic strains and a magnetic field in the body. The characteristics of the stress–strain distribution and induced magnetic field are determined; and their singularities in the neighborhood of the crack are analyzed. Formulas for the stress intensity factors of the mechanical and magnetic fields near the crack tip are presented [ABSTRACT FROM AUTHOR]