CEN/TS 15901-1:2009

This Technical Specification describes a method for determining the skid resistance of a paved surface by measurement of the longitudinal friction coefficient LFCS. This Technical Specification covers the operation of the Road Surface Tester of arsenal research (RoadSTAR). The method "RoadSTAR” provides a measure of the skid resistance properties of a bound surface by measurement of the longitudinal friction coefficient using a continuous reading car sized braked wheel fixed slip device. The method "RoadSTAR” provides skid resistance measurements of pavements by using the modified Stuttgart skiddometer (Stuttgarter Reibungsmesser). RoadSTAR utilizes a measurement representing the steady-state friction on a braked test wheel at a slip ratio of 82 % (for standard conditions), 37,5 %, 50 %, 75 % (for comparison measurements), with locked wheel or under ABS-braking conditions (for research measurements). The test wheel is dragged over a pre wetted pavement surface under controlled load and speed conditions while the test tyre is parallel to the direction of motion and perpendicular to the pavement. NOTE Three different slip ratios are retained in order to use the same slip speed for the three different nominal testing speeds of 40 km/h, 60 km/h and 80 km/h for comparison measurements. The common slip speed is chosen equal to 30 km/h: - for a testing speed of 40 km/h a slip ratio of 75 % should be applied; - for a testing speed of 60 km/h a slip ratio of 50 % should be applied; - for a testing speed of 80 km/h a slip ratio of 37,5 % should be applied. A machine conforming to the general characteristics of the RoadSTAR and the specific provisions of this Technical Specification should be used for the tests. In addition to friction measurements, to estimate the macro texture of the pavement surface, a laser system is used. This system is placed in front of the test wheel in order to be able to measure macrotexture (mean profile depth – MDP) on the dry surface and o