T. Huemer, W. Liu, J. Eberhardsteiner, G. Meschke, H.A. Mang:
"Sliding Behavior of Rubber on Snow and Concrete Surfaces";
in: "Deutsche Kautschuk-Tagung 2000", Deutsche Kautschuk-Gesellschaft e.V., Nürnberg, Germany, 2000, 135 - 137.
Over the last years great efforts were directed to the numerical description of the sliding behavior of rubber blocks on various surfaces by means of the Finite Element Method (FEM). Two major mechanisms of the load transfer of traction forces can be observed depending on the characteristics of the sliding surface. On "soft" surfaces, i. e., snow surfaces, the penetration of the sliding surface by rubber blocks results in a resistance against sliding motion. This resistance permits the transfer of traction forces. Such a mechanism may be viewed as an edge effect. On "hard" surfaces a frictional mechanism is responsible for the transfer of the traction forces. In this presentation details of different effects of both mechanisms are explained. For both of them appropriate numerical models were established.
A constitutive model for snow-type materials was developed. It can be described as a viscoplastic "critical state" material model which is characterized by two hardening/softening mechanisms and a set of yield functions, i. e., multi-surface yield functions, formulated within the algorithmic framework of finite deformation elasto-viscoplasticity. Based on experimental data from uniaxial compression tests, hydrostatic tests, and creep tests of snow, the calibration of the material parameters was performed.
The frictional behavior on "hard" surfaces was taken into account numerically by means of a friction law depending on the sliding surface, normal pressure, sliding velocity, and the environmental temperature. Therefore, a comprehensive experimental investigation with the so-called Linear Friction Tester (LFT) was performed. This testing device was especially developed to determine the frictional behavior of rubber blocks on various surfaces under different conditions of loading, temperature, and sliding velocity. The experimental results were directly used to determine the parameters of the proposed friction law.
Keywords: friction, concrete, rubber, contact, tire, experiment, friction, ice, numerical, surface