Chapter

The Deformation Behavior of Modern Antifriction Polymer Materials in the Elements of Transport and Logistics Systems with Frictional Contact

Authors:
  • Institute of Continuous Media Mechanics of the Ural Branch of Russian Academy of Science
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Abstract

The deformation behavior of two models of spherical bearing of bridge spans was considered in an axisymmetric formulation as part of the work: with and without grooves with lubricant. Two modern antifriction polymers were considered as sliding layer materials: modified PTFE and antifriction composite material based on PTFE with spherical bronze inclusions and molybdenum disulfide. The physicomechanical and frictional properties of the antifriction spherical layer materials were obtained experimentally by the scientific team of Alfa-Tech LLC and Institute of Continuous Media Mechanics of the Ural Branch of Russian Academy of Science. The approximation of the experiments results the dependence of friction coefficient on the pressure was performed and functions approximating the experiments results with a maximum error of 2.3% were obtained. The approximating functions were used to determine the friction coefficient at pressures >54 MPa acting on the spherical bearing. A series of numerical experiments aimed at identifying the qualitative and quantitative patterns of the deformation behavior of the spherical thin sliding layer materials was carried out as part of the work: contact pressure, contact tangential stress, contact status. Comparison of settlement of numerical models of spherical bearing with a modified PTFE layer and experiments data was performed in the work. It is established that the model taking into account grooves with a lubricant has a minimum settlement error under the frictional properties of the interlayer material declared by the manufacturer, which is approximately 8.44%. The settlement error for all considered bearing models is more than 15% with considering frictional properties of antifriction materials obtained experimentally.

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... The technical state of bridge support structures has a significant influence on the operation of the bridgework and may lead to unfavorable consequences [12,20]: the partial or complete destruction of bridge spans, supports, or the work as a whole. One of the actual directions of research in the field of transport and logistics systems is the analysis of the operation of support structures of bridge spans [18,21] and the influence of the geometric configuration of their components on the deformation behavior of structures [22][23]. Active research of support structures with a spherical segment with a polymeric material layer is being carried out. ...
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