T. Huemer, J. Eberhardsteiner, W. Liu, H.A. Mang:
"Experimental and Numerical Investigation of the Friction Behavior of Rubber Blocks on Concrete and Ice Surfaces";
in: "Constitutive Models for Rubber", L. Dorfmann, A. Muhr (Hrg.); Balkema, 1999, S. 139 - 144.
Up till now most on the work of the development of tires has been done empirically. The construction and testing of prototypes of tires is a rather expensive and time-consuming procedure. Therefore, in the last years, great effort and progress were made in the numerical simulation of the mechanical behaviour of tires by the Finite Element Method (FEM). In addition to appropriate element technologies and suitable material models for realistic numerical simulations, it is important to capture frictional effects of rubber correctly. Application of the Coulomg friction law was shown to be inadequate. This contribution is focused on the experimental and numerical investigation of the frictional behavior of rubber blocks on concrete and ice surfaces.
The experimental investigation is performed with a special testing device (linear friction tester, LFT). Friction coefficients are determined under different conditions for sliding velocity, pressure of the rubber blocks on the surface, and environmental temperature. The testing device and the testing scheme as well as selected results will be presented.
For numerical simulations, a friction law dependent on normal pressure and sliding velocity is used. The model parameters are calibrated by using different experimental results. The implementation of the friction law for 2D contact analyses in several multi-purpose finite element codes is illustrated by means of examples.
Keywords: friction, rubber, tire