In this post you will learn about what is bitumen, meaning, definition, types and uses of bitumen.
Table of Contents
Bitumen Definition
Bitumen is the binding material present in asphalt, which is a mixture of bitumen and aggregate (such as gravel, sand, or crushed stone) used for paving roads, runways, and other surfaces.
Sometimes it is also called mineral tar. Bitumen is made by partial distillation of crude petroleum.
Bitumen Meaning
Bitumen is chemically a hydrocarbon and insoluble in water. But it entirely dissolves in alkalies, alkaline carbonates, benzol, chloroform, bisulphide, naptha, coal tar, petroleum spirit, and oil of turpentine.
It holds 87% carbon, 11% hydrogen, and 2% oxygen (by weight). It is produced in a solid or semi-solid state and black or brown in color.
The refining of crude oil produces a thick, viscous, black or dark-colored, sticky substance known as bitumen, which is commonly used as a binding material for road construction, roofing, and waterproofing.
The primary component of bitumen is asphaltene, which is a complex mixture of hydrocarbons. It is soluble in many organic solvents and is thermoplastic, which means it can be softened by heat and hardened by cooling.
In road construction, a mixture of bitumen and aggregates, such as gravel and sand, is created to make asphalt concrete. This material is used as a surface for roads, airport runways, and parking lots.
For roofing, bitumen is used as a waterproofing agent and as a coating for roofing felt. Additionally, bitumen is utilized in the production of various industrial products, such as adhesives, sealants, and insulating materials.
In-Depth Study
Bitumen is a complex material. Due to the different range of compounds, it has different features. For this reason, bitumen tests are introduced to the industry.
With help of penetration and viscosity tests, bitumen is classified based on its physical properties. These two tests also measure the compatibility of bitumen.
Bitumen penetration test has been used since the early twentieth century. It is graded bitumen based on its hardness and softness.
After many years, the viscosity grading system is used based on measuring bitumen viscosity. It measures viscosity by viscometer in two different temperatures of 60 C and 135 C.
For forecasting the temperature at which bitumen starts to melt, the softening point of bitumen is used. It measures the softening point with a ring and ball apparatus.
Bitumen binder in asphalt must ductile enough to tolerate the traffic load and temperature difference. As a result, a ductility test is a good way to measure this property.
One of the dangers in the transportation and storage of bitumen is the risk of ignition. As a result, the importance of the Flash and Fire Point test is raised.
Bitumen Tests
Here I am attaching the image file of 10 major bitumen tests.
Types Of Bitumen:
The general forms of bitumen are as follows:
1. Bitumen Emulsion:
It is a liquid compound that comprises a large amount of bitumen in the aqueous medium. It is suspended by some suitable stabilizing agents in the aqueous medium.
2. Cut-back Bitumen:
This form of bitumen is produced by fluxing asphaltic bitumen in the existence of some liquid distillates of petroleum or coal tar. Cut-back bitumen can be utilized as bitumen paint in cold.
3. Blown Bitumen:
Blown Bitumen is a special form of bitumen produced by passing air under pressure at a high temperature. This type of bitumen can be utilized as heat insulating material, roofing and damp-proofing felt, producing asphalt pipe and joint fillers, etc.
4. Plastic Bitumen:
It consists of bitumen thinner and appropriate inert filler (40%-45%). Plastic bitumen can be utilized for filling cracks in masonry structures, stopping leakages, etc.
5. Straight Run Bitumen:
Straight run Bitumen is acquired by distillation of the bitumen to a definite viscosity or penetration without further treatment:
Application Of Bitumen
- Road and Highway Construction.
- Runway construction.
- Hydraulics & erosion control Catchment areas, basins.
- Dam groutings.
- Dam linings.
- Embankment protection.
- Dam linings.
- Embankment protection.
- Ditch linings.
- Reservoir linings.
- Jetties protection.
- Dyke protection.
- Swimming pools.
- Waste ponds.
- Water barriers.
- Mattresses for levee & bank protection.
- Membrane linings,
- Waterproofing.
- Revetments.
- Sand dune stabilization.
- Drainage gutters.
- Backed felts.
Closing Thought
As we know bitumen is a cheap material, it is widely used to make flexible pavement. It is used to minimize the cost and durability of roads.