Range of the Applicability of the Wilkins Method to the Investigation of the Dynamic Stress-Strain State of Anisotropic Elastic Axisymmetric Shells

The exactness and stability of the Wilkins method in the investigation of the stress-strain state of axisymmetric anisotropic elastic shells, including thick-walled ones, have been studied for different values of artificial viscosity, pulse load rise and fall time, and different deformation process durations. A comparison of numerical calculations, performed by means of an application software package developed by V. A. Romashchenko on the basis of the Wilkins method, with experimental results, known numerical data, and with calculations using the computation kernel LS-DYNA 3D has been carried out.     

Analytical Calculation of Large-Scale Deflection of Pulse-Loaded Elliptic Plates

Large deflections of pulse-loaded elliptic and round plates made of hardenable elastoplastic materials are investigated analytically using an energy-based approach. Formulas that are convenient for engineering design have been derived.     

Realization of high pressures and temperatures in the gas phase of a bubble liquid flowing through a nozzle

A steady flow of a bubble gas-liquid mixture in a nozzle having a circular cross section has been investigated. The possibility of realization of superhigh temperatures and pressures in the gas phase of the mixture in the region near the smallest cross section of the nozzle has been analyzed. The influence of the initial radius of the flow and the volume content of bubbles, determining the volumetric rate of flow of the liquid supplied to the nozzle, on the pattern of the flow has been considered. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 6, pp. 134–137, November–December, 2007.     

Penetration of a thick plate by a slightly deformable long rod

A numerical simulation has been performed for the high-velocity deep penetration of a slightly deformable long rod into a thick plate. The main features are examined for the multistage rod retardation, and a study is made on how the impact velocity affects the characteristic parameters. An analytical model is formulated for the interaction, which is convenient for engineering use. The calculation agrees well with available experiments.Translated from Problemy Prochnosti, No. 10, pp. 63—70, October, 1993.We are indebted to Professor Sh. U. Galiev for participating in the formulation and for fruitful discussions.     

Construction of Constitutive Relationships of the Deformation Theory for Simple in Noll's Sense Hardening Materials with Elastoplastic Behavior

Based on the theory of simple hardening materials with elastoplastic behavior, the general constitutive relationships of the deformation theory of plasticity are mathematically strictly constructed for arbitrary continuous, piece-wise continuously differentiable deformation trajectories, any strains and symmetry types of the material properties. Two conditions under which this is possible are considered. The approaches to a strict specialization of general constitutive relationships of the deformation theory of plasticity have been developed by imposing restrictions on the material strains, deformation processes and properties. In this case, the restrictions on the properties of materials formalize the data obtained in the experimental investigations. A series of both new and known constitutive relationships have been constructed that are arranged into a hierarchy according to the level of complexity of the response to deformation. The area of applicability of the derived physical equations has been defined. Special attention has been given to the modeling of finite and infinitesimal strains of isotropic materials. __________ Translated from Problemy Prochnosti, No. 6, pp. 35 – 49, November – December, 2005.     

Modeling elastoplastic deformation processes along paths in the form of two-branch breaks

Institute of Strength Problems, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Problemy Prochnosti, No. 7, pp. 7–12, July, 1989.     

Probabilistic modelling of safe crack growth and estimation of the durability of structures

Probabilistic models of crack growth are considered at the macro-level of material deformation. These probabilistic models have parameters that can be determined from a fracture mechanics approach. Results from statistical analyses of defects in welded joints show that it is possible to use a two-parameter Weibull distribution as a basic model for the distribution of defect size. On the basis of a Monte Carlo numerical simulation of crack growth, one can construct complete probabilistic diagrams for structural integrity. These diagrams are the basis for designing structures containing defects.