FREE AND FORCED VIBRATIONS OF SHELLS OF VARIOUS SHAPES, TAKING INTO ACCOUNT THE VARIABILITY OF THE NON-LINEAR ELASTIC MATERIAL

https://doi.org/10.34031/2618-7183-2020-3-1-70-75
The article considers issues of shell vibrations, which are widely used in various industries and construction. Shells serve as elements of building structures with large spans.
The chapter “Introduction” discussed issues related to the use of shells in all areas of industry, in aviation, rocket and space technology, railway transport, in the oil and gas industry and provides examples of shells for use in ceilings of circuses, stations, hangars; in industry: shells of rotation used as tanks, containers, columns, reactors, etc. In the section “Materials and research methods” free and forced vibrations of shells of variable thickness made out of nonlinear elastic material reviewed. In shell calculations the Kirchhoff – Law hypothesis was used. It was found that, during vibrations, the shells experience relative deformation of elongation and shear of the surface with coordinates (x, y), as well as bending and torsion strains. It is established that vibrations in the shells lead to a rotation of the main directions of elasticity and regarding to the adopted coordinate axis to angle θ, and the elastic constants of the material depend on the elastic constant Biy – the main directions of the nonlinear elastic shells.
When solving the system of equations of motion of the shell relative to the displacements arising in it during vibration, based on theory R and various methods. The values of the dimensionless frequency parameter for a spherical shell taking into account changes in its curvature, variability and thickness of elastic properties are obtained.
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Sadygov I.R. Free and forced vibrations of shells of various shapes taking into account the variability of thickness of the non-linear elastic material. Construction Materials and Products. 2020. 3 (1). P. 70 – 75. https://doi.org/10.34031/2618-7183-2020-3-1-70-75