What Is Bitumen Types, Applications & Test
Bitumen binder is the main material in road construction and waterproofing. It acts like glue. In road construction, it bonds the aggregates to each other. In waterproofing, it insulates the surface from penetration of the water.
Altogether, this sticky material has different types and grades. It has different applications and different tests.
If you are interested in knowing more details about Bitumen, read the article below.
Bitumen Production Process
Generally, bitumen can be produced by 4 methods. All of these methods have their own different processes:
- Air Blowing
- Solvent De-asphalting
Bitumen has 2 groups:
Refined Bitumen can be produced in the crude oil refinery and Natural Bitumen or Gilsonite can be extracted from the mines.
The refined Bitumen can be classified into different types. The main types of refined bitumen are as below:
- Penetration Grade Bitumen
- Viscosity Grade Bitumen
- Oxidized or Blown Bitumen
Each of these types has its own grades. To clarify this classification, pay attention to the below:
Penetration grade bitumen is the most common grade of bitumen that is highly demanded in the construction industry. It can be used in different types of weather conditions. Penetration grades are classified based on the needle penetration in the bitumen penetration test. The numbers in each grade show the range of needle penetration in the sample that represents the bitumen consistency.
The Penetration grades of bitumen are including:
Viscosity Grade bitumen is one the most used bitumen in India. It is the substitution of penetration grades in this country. Viscosity grades are classified based on the viscosity value in both 60 C and 135 C which are more reliable than Penetration grades. Below are different grades of viscosity bitumen:
Oxidized or Blown Bitumen:
Oxidised Bitumen has a wide variety of grades. The most common grades are 85/15, 85/25, 95/25 and 115/15. This type of bitumen can be used as an additive in road construction to improve asphalt performance.
Besides the main grades of bitumen, there exist two other types of bituminous products:
- Emulsion Bitumen
- Cut back Bitumen
Emulsion and cut back are liquid bitumen. These types of bitumen cannot be used as a binder to bond the aggregates, they can be used in road construction to coat the surface and maintain the surface of the road from damage.
Emulsion Bitumen is the combination of bitumen, water and a type of emulsifier. Due to the anionic or cationic emulsifier, this type of bituminous product can be classified into cationic or anionic emulsion bitumen.
Cut-back bitumen is the combination of bitumen and a petroleum solvent, Kerosene or Naphtha.
As stated in the opening, the main application of bitumen is in road construction and waterproofing. In road construction, we have two types of paving:
- Flexible Pavement
- Rigid Pavement
In Flexible Pavement, there exist different main layers and sub-layers. The main layers are Sub Base Course, Base Course, and Surface Course and the sub-layers are Tack Coat, Binder Course and Prime Coat. Besides these layers, there exist different types of protective asphalts. These asphalts can maintain the road surface from any damage.
In the Infographic below, you can see more details about different types of bitumen that can be used in different layers of flexible pavement and protective asphalts.
Since Bitumen has a significant role in road construction, its quality is important. Low-quality Bitumen which is damaged bitumen cannot bond aggregates well. When poor quality bitumen is used, the road surface deteriorates and these damages remain for a long time.
So before using bitumen in road construction, it is necessary to become aware of the bitumen quality by Bitumen Tests.
Below, you can read the bitumen tests’ names:
- Penetration Test
- Ductility Test
- Softening Point Test
- Viscosity Test
- Spot Test
- Drop in Penetration after Heating Test
- Flash and Fire Point Test
- Loss on Heating Test
- Float Test
- Specific Gravity Test
- Solubility Test
Thanks for your attention. You can read more about bitumen in the link below: