This standard specifies the method for measuring relative wet grip braking performance for truck & bus tyres.
The test method of comparison with standard reference test tyre is adopted in this standard.
This standard applies to new truck & bus tyres.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6326 Tyre terms and definitions (GB/T 6326-2014, ISO 4223-1: 2002, NEQ)
GB 9744 Truck tyres
ASTM E303 Standard test method measuring surface frictional properties using the British pendulum tester
ASTM E965 Standard test method for measuring pavement macrotexture depth using a volumetric technique
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 6326 and the following apply.
3.1
candidate tyre
tyre that is evaluated by testing
3.2
standard reference test tyre; SRTT
a set of special candidate tyres that are used as a benchmark in an evaluation system These tyres usually have carefully controlled design features to minimize variation and they are produced, controlled and stored according to the relevant standards
3.3
control tyre
tyre which is used to indirectly obtain the comparison result between candidate tyre and standard reference test tyre by comparing with the candidate tyre and then the standard reference test tyre when the candidate tyre and the standard reference test tyre cannot be compared on the same vehicle
3.4
braking force of a tyre
longitudinal force, expressed in newtons, resulting from braking torque application
GB/T 35163-2017 The following standards are cited：
