Abstract— This work presents an experimental investigation and a finite element analysis on mechanical behavior, in particular, the deformation behavior, fatigue performance and failure modes of metallic materials such as a grade 8.8 alloy steel. First, the mechanical tests of the base alloys and their welded joint were conducted, and the stress-circulatio curve with a survival rate was obtained. Second

Abstract— The problem of constructing a guaranteeing control for a shock isolator that protects an object on a movable base from impacts to which the base is subjected is considered. The impact disturbance of the base is not known in advance and is modeled by the time history of the acceleration of the base. It is assumed that the impact acceleration is bounded, does not change in direction, and its

Abstract— In this article, we consider flexural (bending) waves propagating in a homogeneous beam fixed on a nonlinear elastic foundation. The dynamic behavior of the beam is determined by Timoshenko’s theory. The system of equations describing the bending vibrations of the beam is reduced to a single nonlinear fourth-order equation for the transverse displacements of the beam median line particles

Abstract In mechanical autonomous conservative systems that admit a partial integral, there are sometimes stationary motions that exist both with and without a partial integral. A system is considered in which the Hess integral exists when the Appelroth equality is satisfied and the stationary motion is distinguished, which takes place even without the Appelroth equality. In the article, the stability

Abstract— When two anisotropic rough surfaces contact, the interface is shown as the contact anisotropy or contact isotropy, which closely relates to the asperity contact azimuthal angles on the microscopic scale. The interfacial contact anisotropy/isotropy will influence the normal contact stiffness and damping of mechanical joints. A normal contact stiffness and damping model between two anisotropic

Abstract— The spatial 3D gyrocompass, developed by the author to control the angular position of an orbiting spacecraft (SC), makes it possible to create an orientation system based on it, operating both from an Earth orientation device (EOD), and from an astro sensor (AS), or any another sensor without changing the basic structure of the algorithm. Such a system can be called a hybrid orientation

Abstract— The study is based on the results of creep up to destruction tests of tensile specimens of titanium alloy VT6 at 600°C, into which hydrogen of various concentrations was previously introduced. In this work, a theoretical generalization of the data obtained for a non-stationary complex stress state is carried out. The modeling of the creep of a cylindrical shell up to destruction with two

Abstract— The fundamental questions of the theory of new gyroscopic sensors based on an elastic axisymmetric resonator, namely, a solid-state wave gyroscope (SWG), in a hemispherical quartz resonator of which simultaneously can excite and exist various working forms (modes) of standing waves of elastic vibrations are discussed. In the proposed study, fundamental questions of the theory of new gyroscopic

Abstract— The problem of analytical synthesis of functions approximating the dependence of the length of the geodetic line on the navigation parameters of its start and end points for the spheroid and the Earth sphere has been solved. The dependences approximating the length of the geodetic line are determined for both the reduced and geodetic latitudes. Expressions are obtained for the azimuth of

Abstract The propagation of G-type wave in a viscoelastic stratum lying over a non homogeneous fibre reinforced elastic half space is examined with possible applications. The dispersion equation and maximum energy flow around the stratum are computed in a closed form applying the technique of infinite determinant and Laplace transform under appropriate boundary conditions. The dispersion equation agrees

Abstract— The problem of active suppression of vibrations of an elastic panel moving longitudinally in an ideal fluid flow is considered. The dynamics equation of the panel includes the fluid response and external mechanical action that serves to implement the damping process. The conditions of extremality of lateral vibration damping are derived and the efficiency of the optimal distribution of the

Abstract— Novel approximate methods of wave propagation analysis are developed for functionally graded cylinders with mass and elastic parameters described by continuously differentiable functions of radius. Two of these methods relate to embedding of boundary value problems into corresponding initial value problems and the third method demonstrates methodology of discretization of the physical parameters

Abstract— A new mathematical model of modified couple stress thermoelastic (MCT) diffusion is constructed where non-local and dual-phase-lag effects are considered. These impacts are analyzed due to thermomechanical loading. Governing equations are simplified by using Laplace and Fourier transform techniques. Normal and thermal loading of ramp-type are taken into account to demonstrate the application

Abstract— Linear bending of a cantilever bar under comprehensive pressure and longitudinal force is considered in static and dynamic settings. The transverse distributed force on the rod, which arises during bending as a result of the formation of the difference between the areas of the convex and concave parts of the surface, is taken into account. The compressive force can be constant in direction

Abstract— The article deals with the problem of stability of an infinitely long cylindrical shell, located in an absolutely rigid medium, compressing the shell so that it can lose stability only by deforming into an inner cavity. Using the equations of the nonlinear theory of shells, which takes into account from nonlinear effects only changes in the radii of curvature of the middle surface of the

Abstract This paper is dedicated to the mathematical modeling of torsional surface waves in a heterogeneous monoclinic crystal cladded with a void type porous layer and gravitating viscous-sandy-elastic semi infinite substratum subjected to imperfect corrugated boundary surface. The model is solved analytically by using an implicit separable variable technique together with a Whittaker’s function and

Abstract— Exact solution of axisymmetric wave propagation problem in radially and functionally graded circular cylinder made from combination of isotropic and transversely isotropic materials is obtained. This solution is based on exact relationships derived by C. Chree and exact continuity and boundary conditions formulated for the problem with arbitrary number of concentric circular layers. The solutions

Abstract— Uniaxial tensile tests of GH3128 on a Gleeble-3800 thermal-mechanical physical simulation machine were carried out under the temperature and stress of 850°C, 900°C and 950°C, 50 MPa, 65 MPa, 80 MPa and 100 MPa, respectively. According to the test data, two creep constitutive equations based on strain-time creep model and Norton power law creep model were obtained. By comparing the calculated

Abstract— The plane motion of a solid in a uniform gravity field is studied. The solid is suspended on a weightless inextensible thread, which remains stretched during the motion. It is assumed that the length of the thread is large (\(\sim {{\varepsilon }^{{ - 1/2}}}\)) and the distance from the point of solid suspension to its center of gravity is small (~ε). The equations of motion are presented

Abstract— A number of samples have been designed and manufactured - perforated plates with lattices of unequal periods and different orientations. Tensile tests of the samples were carried out, their effective elastic moduli were obtained. A mathematical model has been built and corrected, and a successful comparison of experimental and theoretical results has been carried out.

Abstract— In 1891, Professor George H. Brian demonstrated the effect of standing wave precession in an elastic axisymmetric shell rotating about an axis of symmetry. To explain the effect, Brian turned to a mathematical description of elastic vibrations of a thin circular ring. As a result, he obtained a formula connecting the constant angular velocity of rotation of the ring in its plane with the

Abstract— A technique has been developed for the use of artificial neural networks to describe the nonlinear relationship between the components of stresses and strains (tensor equation of state) and the onset of plastic flow (homogeneous nucleation of dislocations) in metal single crystals by the example of aluminum. Datasets for training neural networks are generated using molecular dynamics (MD)

Abstract— The size effect of the strength of structurally inhomogeneous materials is manifested, in particular, in the dependence of the failure load on the size of the stress concentration zone that occurs near material or geometric inhomogeneities (inclusions, pores, cutouts, fillets). Although the size of the stress concentration zone is determined primarily by the size and shape of the inhomogeneity

Abstract— An exact analytical solution to the problem of dynamic expansion of a spherical cavity in an elastic medium (soil) with an arbitrary constant speed is obtained. It is assumed that this speed can be large, up to the velocity of propagation of bulk waves in the medium, and therefore the boundary conditions must be set on the moving boundary. The found solution makes it possible to judge the

Abstract— The method of mathematical modeling is used to study the flutter of an elliptical plate in a plane for different directions of the incoming flow’s angle of attack. For the numerical simulation of unstable vibrations of the plate, an effective numerical algorithm without saturation is proposed, which makes it possible to obtain an acceptable accuracy in the approximate solution on a sparse

Abstract— The concept of phononic crystals is employed to improve vibroacoustic properties of truss core sandwich beams. A typical sandwich beam exhibits a flexural wave bandgap, as well as significant vibration attenuation, from 968 to 2132 Hz without adding any structure. Therefore it has big advantages of easy manufacturing and lightweight over sandwich beams with local resonators, which include

Abstract— The problem of finding equilibrium configurations of a heavy inextensible closed thread (chain) on a smooth surface is considered. The surface is a one-way bond for the thread and is either a circular cone, the axis of which is parallel to the vertical (gravity), or a sphere. It is shown: 1) for a cone, equilibrium non-horizontal configurations of a thread-chain are possible only when the

Abstract— A mechanical system with two rotational degrees of freedom is considered. The mathematical model is presented in the form of a fourth-order dynamic system. A numerical–analytical iterative method is proposed for finding solutions close to periodic, corresponding to the autorotation modes of a mechanical system. Fixed points (including saddles) of the system averaged over two angles are used

Abstract— The article presents a new interpretation of the basic geometric concept of general theory of relativity, according to which gravity is associated not with the curvature of the Riemannian space generated by it, but with deformations of this space. Using such a formulation, the linearized equations of the general theory of relativity for empty space turn out to be analogous to the compatibility

Abstract Proper generalized decomposition (PGD), an advanced numerical simulation method, has been successfully used as a model reduction method in many fields. In this study, functionally graded materials are analyzed using the Airy stress function method, and a compatible equation representing the stress function is obtained. PGD is used to solve a compatible equation, which is a complex high-order

Abstract— An analytical solution for high-pressure torsion of a cylindrical sample placed in a rigid gasket is obtained. The sample material is assumed to be isotropic ideally plastic. The dependence of the yield strength on pressure is taken into account. A non-associated plastic flow model is used, which includes the Tresca plastic potential and the Mohr–Coulomb yield condition. The solution predicts

Abstract— Diagnostics of defects is the first step towards their “healing”—partial or complete elimination of the effect of defects on the stress-strain state of the structure. This article considers the “healing” of cavity defects by filling with various materials. Evaluation of the effectiveness of such healing is carried out according to vibroacoustic criteria using the examples of annular defects

Abstract— The thermomechanical properties of high-density polyethylene samples (Тmlt = 142°С) subjected to plastic deformation under a pressure of 0.5–1.0–2.0 GPa at room temperature have been investigated on an anvil-type high-pressure apparatus. The decrease in the thickness of deformed samples upon heating depends on the processing pressure and the state of the compressive anvils, namely, grounded

Abstract— It is shown that train starting when using elastic car couplings is much easier than with non-deformable ones. Moreover, the greater the number of cars, the greater the advantage of the first variant over the second one.

Abstract— Relevant problems on modeling mechanisms with elastic links imply the improvement of existing formalisms and algorithms for dynamic analysis, synthesis, and optimal control of the considered class of systems. At the same time, modern research in this area is mainly focused on increasing the speed of computational algorithms without decreasing in the accuracy. If elastic multi-link dynamical

Abstract— The movement of a small wind power plant with a vertical axis of rotation in a stationary air flow is considered. The plant consists of two coaxial Darrieus rotors rotating in opposite directions. On the shaft of one of them, the rotor of the generator is rigidly fixed, on the shaft of the other, the stator is placed. A closed few parametric mathematical model of a wind turbine is constructed

Abstract— Performance measures have been utilized for numerous applications in robotics research. In this paper, the manipulability and dexterity indices have been focused. These indices have been used successfully when parallel robots have either completely revolute or prismatic joints. But, in a manipulator with both revolute and prismatic joints, these may not be used because of the dimensional

Abstract— The perforation along the normal by a spherical rigid striker of a package of several plates with different strength properties was experimentally investigated. The influence of the presence of additional free surfaces (delamination) and the order of arrangement of plates with different strength properties in the punching package on the pereforation process has been studied.

Abstract— A modification of the statement of the problem of statics of a homogeneous isotropic incompressible material at finite deformations is proposed, taking into account thermal expansion. The influence of thermal expansion in an inhomogeneous stationary temperature field on the inhomogeneous stress-strain state of a solid is considered by the example of a cylindrical sleeve subjected to a finite

Abstract— Differential equations for potentials are considered that ensure the fulfillment of the basic vector differential equation of the linear theory of elasticity in the case of a harmonic dependence of the displacement field on time. An alternative scheme for splitting the vector differential equation of the linear theory of elasticity into unrelated equations is developed. It is based on the

Abstract— Approaches to physical modeling of ice as a material and ice cover as a specific natural object during model tests of ships and offshore engineering structures in ice tanks are considered. The analysis of methods for obtaining ice models partially satisfying the conditions of the similarity theory is carried out. New methods of modeling and obtaining ice cover are shown, which satisfy the

Abstract— The solution of dynamic problems on longitudinal impact of a system of homogeneous rods in a nonlinear formulation presents, as is known, significant mathematical difficulties. The existing approaches have a rather limited application, mainly due to the significant approximation of the solution of the problem. In addition, such approaches involve an extensive mathematical apparatus, which

Abstract— A system with two degrees of freedom in the case of a double natural frequency is considered. The unperturbed system consists of two independent oscillators. The system coordinates describe an elliptical trajectory with four orbital elements. An analysis of the action of linear perturbations (forces) on the orbital elements is carried out. Perturbations are subdivided into six types of forces

Abstract— The previously proposed piecewise-linear form of the constitutive relations for the relation between stresses and strains has been applied to the description of the processes of cyclic high-temperature deformation of metals and alloys in the regions of linear and nonlinear viscoelasticity. The behavior of two alloys is investigated: the high-temperature and heat-resistant KhN55MVTs alloy

Abstract— The choice of a transport and launch container (TLC) for analyzing the stress concentration in its elements does not reduce the generality of the proposed methodology for solving problems for other thin-walled structures. The TLC is, as a rule, a cylindrical glass with a spherical bottom, at the pole of which there is a rigid mounting plate. The TLС is loaded by the internal pressure during

Abstract— A solution is found by the method of perturbations with an accuracy up to values of the second order of smallness, which describes the state of an inhomogeneous elastoplastic thick-walled pipe under the action of compressive forces. Deviations of the contour of the cross-section of the pipe from the circumference and inhomogeneity of the material are characterized by independent small parameters

Abstract— The modeling of a mechanical system with an arbitrary number of links of variable length that are composed of two weightless sections of variable length and a massive absolutely solid rod located between them is considered. The problem on controlling the purposeful motion of a system with an arbitrary number of links of variable length is analyzed. Control is performed by changing the length

Abstract— A spatial construction, which looks like a bellows (or sylphon), composed of flat shells in the form of a regular truncated cone and circular plates hinged inside the bases of the cones, is proposed. The material of shells and plates is elastically orthotropic with radial and tangential isotropic axes. The structure is subjected to longitudinal axial compression, which creates an axisymmetric

Abstract— The problem of the dynamics of a rigid body in the form of a parallelepiped on a plane in the presence of two-dimensional dry friction (generalized model of dry friction Coulomb-Contensou [1]) is considered. Since in this model of friction there are no discontinuities of the first kind in velocity, the problem is mathematically simpler than problems with one-dimensional (according to Coulomb)

Abstract— In connection with the 120th anniversary of the publication of the last volume of A. Poincaré’s book “New Methods of Celestial Mechanics”, the following methods are considered that have arisen since then. 1. The normal form method, which allows one to study regular perturbations near a stationary solution, near a periodic solution, etc. 2. The method of truncated systems obtained with the

Abstract— The method of analytical construction of the control of the spatial motion of a rigid body (control of screw motion, equivalent to the composition of angular (rotational) and translational movements) is being developed in a nonlinear dynamic setting using Clifford biquaternions and dual matrices. The controls provide asymptotic stability in large for any selected programmed spatial motion

Abstract— Based on the analysis of the results of experimental studies of 12Х18Н10Т stainless steel specimens under a rigid (controlled deformation) process of deformation, which includes a sequence of monotonic and cyclic loading modes, some features and differences in isotropic and anisotropic hardening processes under monotonic and cyclic loading are revealed. To describe these features within the

Abstract— The article proposes a numerical method for solving spatial problems of fracture mechanics (method of discontinuous displacements). The advantage of the method is the representation of the solution in the form of a finite series of expansion in terms of the found analytically presented functions. The expansion coefficients are determined from the conditions for fulfilling the boundary conditions

Abstract— To study the influence and selection of rational elastic-dissipative parameters for under wing pylon-mounted engine suspension, a mathematical model of aeroelasticity of a large-sized transport aircraft has been developed by taking into account the kinetic moment of the engine rotors and specially designed engine attachment points to the pylons. It is shown that the elastic-dissipative parameters

Abstract— The need to improve existing and develop new effective technologies for processing metal materials by pressure (including those with severe plastic deformations that make it possible to obtain products with an ultrafine-grained structure), constantly increasing requirements for the accuracy of strength calculations, emerging new materials with complex properties (including gradient materials)

Abstract— The article presents the results of a computational and experimental study on the impact interaction of structured punches corresponding to the design of Russian and foreign small arms ammunition with homogeneous steel and composite armor. Particular attention has been paid to the careful modeling of the behavior of the materials of the punch and the plate under dynamic loading. To confirm

Abstract— We study the stability of a one-dimensional laminated beam which consists of two identical layers of uniform thickness. An adhesive of small thickness is bonding the two layers and creating a restoring force thereby producing a damping called adhesive or structural damping at the interface. It is well-known in the literature that this single frictional damping is not strong enough to stabilize

Abstract— A pseudodifferential operator is constructed that describes the stress field in an anisotropic medium caused by a dislocation with a variable Burgers vector. Under the assumption \({\mathbf{b}} \in {{H}_{{1/2}}}(\Pi ,{{R}^{3}})\), analytical expressions for the energy of circular dislocations with a variable Burgers vector in an elastic medium with general anisotropy are obtained for the

Abstract— This article is the second part of the work, published in the form of two articles. The case, which remained unexplored in the first part, is considered, when for an unperturbed value of the constant of the cyclic integral, the mechanical reduced potential energy is constant with respect to the internal cardan angle. It is proved that in this case, for the majority of device designs, instability

Abstract— The fundamentals of the theory of objective tensor mechanical characteristics are presented: the general concept of objectivity, types of objectivity, simple tensor analogs of mechanical characteristics and simple commutative diagrams connecting them. For objective tensors of the second rank, a general classification of simple diagrams is given, examples of diagrams are given. The mappings