Stress-Strain State of a Corrugated Cylindrical Shell

By using the relations of the Kirchhoff–Love theory of shells and the method of distortion of the shape of the boundary in the process of axisymmetric heating through the thickness of shells according to a linear law, we construct a solution of the problem of statics for a corrugated cylindrical shell in an axially symmetric temperature field under the action of internal pressure.     

Mathematical Description of Perturbations of the Stress-Strain State

We deduce expressions for the variations of initial stresses caused by small perturbations of a basic state of any type (thermal, electric, or magnetic). As a result, we get two kinetically different types of expressions. In the first case, the perturbation of stresses is connected with the perturbation of the stressed state. In the second case, it is connected with small additional strains. In both cases, the perturbation is also connected with perturbations of the other basis parameters of state. The physical meaning of the terms appearing in the proposed expressions is analyzed.     

High-Density Pulse Current-Induced Unsteady Stress-Strain State in a Long Rod

The results of experimental investigations and numerical calculations of the unsteady stress-strain state in a thin steel rod (wire length) prestressed statically below the yield strength upon the passage of a high-density current pulse are presented. The current pulse gives rise to oscillations of axial stresses with a period corresponding to the period of natural longitudinal oscillations of the rod. Maximum compression and tensile stresses are determined by current pulse front duration and its amplitude. A high level of the above stresses in the central portion of the rod brings about local losses of longitudinal stability. The results of numerical simulation of the stress-strain state in the rod upon its heating with a current pulse correspond to experimentally observed effects. A current pulse-induced decrease in the level of initial tensile stresses (at constant strains) produced by static loading points to the development of relaxation processes that are associated not only with heating. To separately evaluate the effects stemming from elastic stress waves in the rod, heating, and immediate current action, further studies would be required.     

Numerical Simulation of the Stress-Strain State of the Rocket Retention Module

Strength of Materials - The paper considers the thermal stress state of the module for retaining the rocket during firing. The high-temperature gas flow leaves the cruise propulsion system and...     

Stress-Strain State of a Thick-Walled Billet in the Case of Deforming Drawing

We present results of the investigation of specific features of strengthening workpieces by deforming drawing. The results obtained make it possible to predict the quality of the treated surface when designing technological processes involving operations of cold axisymmetric plastic deformation.     

Stress-Strain State and Damage in Polymer Parts of Instruments Aboard Artificial Satellites

Strength of Materials - The paper presents a method for determination of the stress-strain state and the level of accumulated damage in polymer parts of the devices aboard artificial satellites...     

Calculation and Experimental Analysis of the Stress-Strain State for Inclined Semielliptical Surface Cracks

Numerical calculation data on the characteristics of linear and nonlinear fracture mechanics are presented. These characteristics help to predict the surface development of studied cracks before their initiation on the surface of a product. In addition, they provide the specified durability and strength evaluation of important elements of equipment with consideration of the kinetics of the local fracture processes along the contours of differently oriented semielliptical surface cracks with consideration of the local dimension of the stress state and their relative depth.     

Experimental and Theoretical Studies on the Nonlinear Stress-Strain State of a Laminated Ceramic Composite

The mechanical response of a laminated ceramic composite specimen to static bending was studied experimentally. A procedure for solving the inverse problem with experimental data on the deformation of a laminated ceramic composite specimen in the form of a beam was developed, which allowed one to evaluate its mechanical characteristics. The nonlinear stress–strain curve for the material of the specimen as a quasi-homogeneous structure was plotted, and similar curves for each of the two materials of the layers forming the composite were also obtained. The stress-strain state of this composite was investigated theoretically, and the results were analyzed.     

Determination of Stress-Strain State and Strength of Structural Elements on the Basis of Strain-Hardening Analysis

We outline the fundamentals of the method whereby the stress-strain state and strength of structural elements loaded along linear paths and small-curvature paths are determined by allowing for strain hardening of material of the structure or plastic indicators attached to it. The method is based on a model of hardening which assumes that during the deformation beyond an elastic range the loading surface separating elastic and elastoplastic deformation ranges changes its shape and shifts in the direction of the vector which connects its center and an image point on the loading path. It is assumed that the material in its initial state is isotropic and the hypotheses for the unified stress-strain curve and for the proportionality of stress and strain deviators are met.__________Translated from Problemy Prochnosti, No. 2, pp. 28 – 48, March – April, 2005.     

Methods for Evaluating the Characteristics of the Stress-Strain State of Seismic Blocks Under Operating Conditions

Strength of Materials - The concept of the vibration and seismic isolation of heavy mining machines, buildings, and structures with rubber seismic blocks is considered. The concept of the seismic...