Viscoelastic and thermomechanical properties of tire rubbers have been studied to predict hysteresis losses during rolling of automobile tires. The temperature dependences of the elasticity modulus and the tangent of mechanical losses obtained by dynamic mechanical analysis and combined tests in the mode of quasi-static cyclic stretching with subsequent relaxation were used for the calculated determination of the deformation and dissipative parameters of 20 rubber compositions. As a basic theoretical description of rubber as a thermorheologically simple material, a linear viscoelastic Prony model is used, for the identification of which the Willams–Landel–Ferry (WLF) temperature-time analogy is used. The advantage of the computational and experimental approach used is the ability to determine the parameters of the WLF equation regardless of the values of other material characteristics. A fairly simple Mooney–Rivlin potential function for an incompressible material is used to describe large elastic deformations of the elastomer under study. The relaxation curve obtained by means of quasi-static tests is applied to assess the adequacy of the constructed mechanical and mathematical model. In particular, the comparison of the experimental relaxation curve with the results of calculations for tread rubber showed a discrepancy not exceeding 15 %. The performed analysis of viscoelastic and thermomechanical parameters of tire rubbers covers (and significantly exceeds in frequencies) the range of operating temperatures and loads of automobile tires. The results obtained can be used in the computational optimization of the composition of materials and the design of automobile tires according to the criterion of rolling resistance and minimizing heat generation in the tire during movement.

A procedure is proposed for calculating the internal profile and optimal distribution of materials for a pneumatic car tire in a mold configuration. To adequately describe the elastic-dissipative properties of tire rubbers and rubber-cord composites, nonlinear elastic deformation Mooney–Rivlin model and viscoelastic Prony model as well as experimental data of static and dynamic tests are considered. An algorithm for finite element analysis of the stress-strain state of a passenger car tire is described in the MSC.Marc software package, and results of numerical solution of applied problems are presented on the tire landing on the rim and its loading with working pressure, as well as on the contact interaction of a passenger car tire with the road surface at maximum operating load at rest and during stationary rolling at a speed of 90 km/h. It was found that the contact loading of the tire when interacting with the road surface does not lead to a significant difference in the deformed state in the zone opposite diametrically to the contact zone from that for a tire mounted on a rim and loaded with excess operating pressure. In this case, the nature of the distribution of strains in the radial section near the contact zone of the tire with the road surface is the same under conditions of compression and stationary rolling. Areas of concentration of equivalent stresses and strains in the bead zone of the tire and in the zone of the edges of the breaker are revealed. For a quick comparison of competing tire designs, it is recommended to calculate the average values of the total strain energy density per wheel revolution. The developed calculation methods make it possible to predict the performance characteristics of automobile tires at the design stage and are tested in the manufacturing of these products.

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Methods are considered for solving design and technological problems at the design stage of the radial tire specification. On the basis of the theory of gridshells, a scheme is constructed for calculating the distribution of materials in the radial section of an uncured and vulcanized radial tire. For a flat method of assembling the radial tire, algorithms for calculating profiled parts are proposed. Algorithms are considered for finding the geometry of the shaping surfaces of the tread and sidewall parts. The boundary-value problem of finding the profile of the molded uncured tire at the second stage of assembly has been solved. A method is proposed for determining the parameters of industrial equipment for tire assembly. The experiments carried out to test the accepted hypotheses of the theory of elasticity are described.