Modeling the Destruction of an Anisotropic Composite Barrier in Interaction with Slender Strikers at an Angle

Journal of Engineering Physics and Thermophysics - A numerical investigation has been made into the interaction of slender (5–20 calibers) steel cylinder strikers with orthotropic compost...     

A Mixed-Approach Analysis of Deformations in Pipe Bends. Part 3. Calculation of Bend Axis Displacements by the Method of Initial Parameters

A problem of deformation of a curved shell loaded by internal pressure, axial force, and temperature difference is discussed. Physical equations are derived whereby the displacements and angles of rotation of the line of centers of mass of cross sections of a shell are related to loading parameters. A general constitutive set of equations for a curved element during its deformation is given. Using a method of initial parameters, an analytical solution is obtained for the differential equations for displacements and angles of rotation of the center line allowing for the action of distributed forces and moments.     

Stress State of Bent Buried Pipelines

The authors consider edge effects in buried pipelines that occur in the region of joining of a straight buried pipe and a bent insert (factory bend, elbow, or an elastically bent segment). The action of those effects results in the appearance of additional bending moments, which are proportional to the difference between the axial force in an infinite straight pipeline and that in a closed-end pipe, and depend on the geometrical parameters of the pipeline and physical-mechanical characteristics of the soil. Specific examples of analysis of elastic interaction of a pipeline with the soil for pipe bends with various radii of the bend arc are offered. It is shown that additional bending stresses may exceed appreciably the stresses from the axial force, and therefore, they should be taken into account when designing and building pipelines. The solution for an elastically bent segment has been obtained and analyzed.     

Effect of the method of activation on properties of zeolite-containing hydrotreatment catalysts

Translated from Khimiya i Tekhonologiy Topliv i Masel, No. 3, pp. 33–34, March, 1992.     

Use of geosynthetic materials in dam construction

Geosynthetic materials in the form of geomembranes, geotextiles, geonets, geomats, geocomposites, etc., are used widely in modern dam construction. The article describes structural elements of dams in which various types of geosynthetics are used and those functions which geosynthetics perform in these elements.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 50–54, October, 1992.     

In situ cleavage mechanism for semiconductor single crystals for ultrahigh-vacuum scanning tunneling microscope

A tecnique for cleaving semiconductor single crystals under ultrahigh-vacuum conditions is proposed. A system for in situ cleavage of samples for ultrahigh-vacuum scanning tunneling microscope (STM) has been developed. STM studies of the surfaces of InAs single crystals with n and p-type bulk conduction have been performed on an Omicron ultrahigh-vacuum facility.     

Finite-element model of temperature conditions in self-propagating high-temperature synthesis of cylindrical blanks

Two-dimensional, nonstationary heat-conduction problems in a system of four finite bodies with an internal mobile heat source of the first kind (burning front) have been solved by the finite-element method. The influence of basic technological factors on the temperature-field parameters in the process of synthesis of TiB-40% Ti alloys has been investigated. It has been shown that for a real technological cycle the temperature field in a blank and a sand shell can be considered to be stationary and homogeneous. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 79, No. 5, pp. 64–73, September–October, 2006.     

Classical Approach to Analyzing the Influence of Edge Boundary Conditions on Stresses and Flexibility of Pipe Elastic Bend

A new analytical method is proposed for the analysis of boundary effect in a pipe bend portion loaded by bending moment combined with internal pressure. The proposed method is based on the simplifying hypotheses, which make possible to represent all deformation- and force-related parameters in terms of the tangential displacement assumed in the form of the Fourier series expansion by the circumferential coordinate. A set of quadric differential equations by axial coordinate containing unknown displacement expansion coefficients is derived. We obtained an analytical approximate solution for a pipe bend portion and precise solution for a straight pipe, which are expressed via Krylov functions. We formulate the application procedure for the method of initial parameter, where the values of tangential and longitudinal displacements, axial and tangential forces are used as boundary conditions. We present the equations relating the above-mentioned parameters in the initial and end sections of the pipe bend portion. The results obtained are compared with the available published data. __________ Translated from Problemy Prochnosti, No. 4, pp. 64 – 94, July – August, 2005.