STUDY ON THE FRICTION PROPERTY OF STUDLESS-TIRES ON ICY ROAD: COMPARISON OF THE FRICTION PROPERTY BETWEEN STUDLESS- TIRES AND LABORATORY PREPARED SAMPLES

In order to evaluate the friction property of studless tires on icy road, we have developed an indoor friction tester, using rubber sample, equipped with an inside drum. Comparing the results obtained by this method and those obtained by the test using studless tires with an indoor tire friction tester equipped with an inside drum which was already reported, we have studied the mechanism of rubber friction and obtained the following results. (1) Results obtained using rubber samples, which show friction property of only rubber, correlate well with those obtaind using block pattern tires without sipe. It was confirmed through this study that a tester equipped with an inside drum using rubber samples is an effective testing method. (2) Effect of only rubber hardness is analyzed as property of adhesive friction by using rubber samples. Friction coefficient can be formulated as multiply adhesion volume by adhesion force using pulse NMR results. F∝Ko•VL•(VL×1/T2L) μ=F/W (3) Effect of load on friction coefficient can be formulated as follows: μ=a•(W/S)+b