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Vol 74, No 4 (2019)
- Year: 2019
- Articles: 4
- URL: https://journals.rcsi.science/0027-1330/issue/view/10041
Article
Effect of the Initial Stage of Strain on the Properties of Relaxation Curves Generated by the Rabotnov Nonlinear Relation for Viscoelastic Materials
Abstract
An equation describing a family of stress relaxation curves with arbitrary strain programs at the initial stage generated by the Rabotnov nonlinear constitutive relation with two arbitrary material functions is derived and studied analytically. The effect of the initial stage duration and shape on the properties of relaxation curves is analyzed. Their deviations from each other and from the relaxation curves under instantaneous load are estimated in terms of material functions and strain programs. The convergence of deviations to zero is proved when the time tends to infinity or when the initial stage duration tends to zero.
83-88
The Mutual Influence of Disk-Shaped Cracks in Three-Dimensional Elastic Space
Abstract
The mutual influence of three-dimensional disk-shaped cracks located in parallel planes of an elastic medium is studied. The medium is under tensile stress directed perpendicular to the crack planes. The cracks are modeled by mathematical cuts of the continuous medium with the possibility of a strong discontinuity of the displacement field on the faces of the cut. The discontinuous displacement method is used to solve the problem numerically.
89-96
Numerical Study of Absolutely Flexible Rods Loaded by Concentrated Forces in an Air or Liquid Flow
Abstract
An algorithm is developed to numerically study the flexible rods (hoses) loaded by concentrated forces and situated in an air or liquid flow. The developed algorithm allows one to solve the static problems with consideration of a liquid flow in a hose. This algorithm can be used to determine an equilibrium rod shape and an axial force in the rod when the velocity vector of the external liquid flow is directed arbitrarily. It is also possible to estimate the rod’s strength.
97-100
101-102