Viscosity grade bitumen is based on fundamental engineerin7g properties and not on empirical properties. It is a performance based grading system.
Viscosity grading system takes into account both low and high temperature susceptibility of bitumen.
Viscosity grade bitumen is very easy to handle as viscosity value at two different temperatures is available, which would enable user to measure accurate mixing and compaction temperatures.
In order to check the quality of viscosity grade bitumen, we only have to conduct 7 no. of tests. This reduces time and cost of testing.
The pavements made from VG bitumen will have better performance, because viscosity value at 1350C gives sufficient idea about mixing and compaction temperature ad as a result pavement life is improved.
Pavements constructed using VG bitumen can take higher traffic load with extreme weather condition.
