Civil Engineering - Building Materials - Discussion

Classification of Bitumen:

Bitumen is classified into 10 grades according to Indian Standards Institution (ISI),
1. VG-10
VG stands for Viscosity Grade. VG-10 is a bitumen grade that has a viscosity of 80-100 centistokes at 60°C.
2. VG-20
VG-20 is a bitumen grade with a viscosity of 160- 220 centistokes at 60°C,
3. VG-30
VG-30 is a bitumen grade with a viscosity of 240- 320 centistokes at 60°C.
4. VG-40
VG-40 is a bitumen grade with a viscosity of 360 480 centistokes at 60°C.
5. VG-50
VG-50 is a bitumen grade with a viscosity of 800- 1000 centistokes at 60°C.
6. VG-60
VG-60 is a bitumen grade with a viscosity of 1200- 1400 centistokes at 60°C.
7.VG-70
VG-70 is a bitumen grade with a viscosity of 2000- 2400 centistokes at 60°C.
8. VG-80
VG-80 is a bitumen grade with a viscosity of 3200- 3600 centistokes at 60°C.
9. VG-90
VG-90 is a bitumen grade with a viscosity of 5000- 6000 centistokes at 60°C,
10. VG-100
VG-100 is a bitumen grade with a viscosity of 8000-10000 centistokes at 60°C.

Conclusion:
Bitumen is classified into 10 grades according to Indian Standards Institution (ISI) based on its viscosity. The grade of bitumen to be used in a particular project depends on the climatic conditions, traffic volume, and type of pavement design.

As per IS 73:2006 Cl-5, there's only 4 grade of bitumen. So, the correct answer will be B.4.

Thanks for the details @Roy.

It should be 4 grades.

Thanks @Roy

As per IS 73:1992. There are six penetration grade (S35, S45, S55, S65, S90&S200). And as per Is73:2013 there are 4 viscosity grade (VG10, VG20, VG30 & VG40).

L thought it is 4 types of grades.

Whoever is saying 6, Please mention the IS code as I couldn't find any IS code which says there are 6 grades.

And please note that the question asked about the NUMBER of grades. It didn't tell anything about the nature of the classification.

Option E is right.

Penetration, viscosity, oxide bitumen grade, bituminous binders prepration, cutback,

Fluxed, modified, emultion, asphalt, performence, natural.

6 grades is correct.