Bitumen 80/100 is one grade of penetration bitumens. And as you know it's name is based on penetration degree. This grade has thermoplastic property which means at high temperature we have softer bitumen and low temperature leads to have harder bitumen.
These features cause bitumen 80/100 be used more in colder areas.
In addition it is used to produce other grades of bitumens like emulsion bitumen, cutback and modified bitumen grades.
