Bearings are the supporting elements of bridges. They perceive vertical and horizontal loads from the bridge span. Spherical bearings are one of the construction common types. The material and configuration of the anti-friction layers determine the bearing performance. The paper performed the contact deformation analysis of spherical bearing elements at a nominal vertical load of 1000 kN. The six types of the spherical sliding layer material are considered: ultra-high molecular weight polyethylene (UHMWPE) from three different manufacturers, modified polytetrafluoroethylene (PTFE), and composite materials by PTFE with two different forms of reinforcing bronze inclusions. Young’s modulus, Poisson’s ratio, and strain curve are obtained experimentally for spherical sliding layer materials. Paper considered the influence of the sliding layer material on the contact parameters and deformation characteristics of the structure with a standard interlayer thickness by 4 mm. Research observed significant the composite interlayer deformation and the appearance of “no contact” zones on the mating surfaces. The option of increasing the sliding layer thickness up to 6–8 mm is considered. A decrease is observed in the maximum level of contact parameters by increase of the sliding layer thickness. The influence of the anti-friction layer materials becomes insignificant on the bearing deformation with an increase of the spherical sliding layer thickness.

The novel results reported here present qualitative and quantitative regularities of the deformation behavior of a spherical bearing with a different location and inclination angle of the antifriction layer. A number of topical problems encountered during the assessment of the performance bearings are considered in the work. The spherical bearings of the bridge span are investigated. Structures are load-bearing elements of transport systems. They perceive thermal power loads from the bridge span. The temperature problem is not considered in this study. In this paper, a comparative analysis of the bridge spherical bearing operation at different antifriction layer locations was performed. Two bearing geometries are considered: the interlayer is pressed in a spherical segment (classical geometry); the interlayer is pressed into a recess located in the lower steel plate. The six modern antifriction materials considered proved suitable to some extent as contact unit sliding layers for various purposes. Additionally, the influence of the inclination angle of the antifriction layer end face on the structure operation for all sliding layer material variants was analyzed. It has been established that the bearing design with an interlayer in the lower steel plate has a more favorable deformation behavior. Changing of the inclination angle of the antifriction layer end face leads to a decrease in the maximum level of contact parameters and deformation characteristics for all the considered structures.

Requirements to critical elements of transport and logistics systems have been increased due urbanization in the territories of Russia and the world. Bridge bearings, which perceive the vertical and horizontal loads from the bridge span, as well as absorb thermal expansion and contraction, shrinkage, seismic disturbances, etc. refer to such elements. Requirements to strength, durability, wear resistance, operation maintenance-free periods, etc., imposed on the bridge bearing are increasing due to a stable growth of loads on the bridge elements and increase in vehicle fleets. Recently, international and Russian companies have been engaged in development of new polymeric and composite materials, which have improved physical and mechanical, frictional, thermo-mechanical and rheological properties and can be used as a thin layer of sliding bearings bridges. A number of problems are outlined in studying material properties and geometric configuration of bridge bearings in order to rationalize the work of its structure. Three topical problems of solid mechanics are reviewed in the work. This is the identification of qualitative and quantitative patterns of the deformation behavior of modern antifriction polymer and composite materials as relatively thin sliding layers of bridge spherical bearings in order to formulate scientifically grounded recommendations for the selection of the interlayer material regarding the study unit operation. This is an analysis of the influence of the sliding layer material physical and mechanical, frictional, thermomechanical and rheological properties on the structure deformation as a whole and the change in the contact zone parameters, in particular. It is an analysis of the influence of the sliding layer geometric configuration on the structure performance. A significant decrease in the area of full adhesions of the contact surfaces, including up to 0, and the occurrence or increase in the area of the divergence of the contact surfaces (no contact) is observed during frictional contact taking into account the lubrication on the mating surfaces. The surface percentage on which the contact surfaces divergence (no contact) is observed decreases, on average by more than 2 times, if the sliding layer thickness is increased.

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Two-dimensional thermo-viscoelastic waves in layered media Dynamic problems of deformation of solids have been the subject of numerous studies in the CIS and abroad. The rejection of a number of simplifying assumptions made in the cited and other published works leads to the need for further refinement and improvement of mechanical and mathematical models describing the kinematics and stress state of both the drummer and the barrier. Further, the axisymmetric collision of a cylindrical indenter with an obstacle in the form of a package of isotropic plates containing free cavities and rigid inclusions is numerically investigated within the framework of the coupled theory of thermoviscoelasticity. Various formulations of the problems of the theory of elasticity and thermo-viscoelasticity are possible. However, the used formulation in velocities and stresses is one of the most universal, since it allows solving the main boundary value problems (including mixed ones) by a uniform way. The paper gives a grid-characteristic scheme and its convergence. In accordance with the theory of A.A. Samarskii, the stability in the energy norm of the grid problem is proved.