Bitumen road feature a surface composed of bituminous mixtures commonly referred as asphalt.
It is a thick, sticky liquid made from natural resources like crude petroleum.
Bitumen is employed in road building because of its unique features over other paving materials.
In this article you’ll learn:
- What is a bitumen road?
- Purpose of bitumen road.
- Merits and Demerits of bitumen road.
- Lots more.
So, if you’re ready to go with a de-shuttering time., this article is for you.
Let’s get started!
What is a Bitumen Road?
Bituminous roads are built of asphalt/bitumen that binds all of the ingredients and is meant as a flexible surface, whereas concrete roads are formed of concretes that are generally a mixture of aggregates, water, cement (with/without additional binders such as fly ash, slag, etc.), and admixtures.
Bitumen acquires certain qualities that are incorporated during the manufacturing process.
The basic material in flexible road repairs and bitumen as a mix offers substantial advantages, leading to its widespread use in road construction.
Purpose of Bitumen Road:
- Bitumen’s physical and chemical characteristics are discovered to be dependent on load level, temperature, and loading time.
- It is highly valued because bitumen has the desired melting point, which assists in surface treatment as well as wearing resistance.
- As bitumen has a low melting point, it may be remelted to its original state.
Bituminous Road Construction Procedure and Steps:
1. Penetration of Bituminous Materials Macadam Road:
The aggregates in this form of the bituminous road are held together by grouting bitumen into the spaces of the compacted particles.
Bituminous roads of this sort are often utilized in thicknesses varying from 50 to 75 mm.
- The grade of bitumen recommended by IRC for this sort of road is 80/100, 60/70, and 30/40.
- Road tars of grades RT-4 and RT-5 can also be utilized.
- Machines and equipment.
- A bitumen heating device is required.
- Distributor of bitumen.
- Roller used in the compacting process.
- Spreader of aggregates.
First, the surface to which bituminous macadam is to be placed is cleaned of dust and other debris.
The road’s grade and camber are appropriately assessed. High permeability surfaces may require a priming layer if necessary.
2. Spreading Coarse Aggregates:
Aggregate laying can be done manually or by machine.
The prefabricated camber profile can be used to produce the required profile in cross-section.
3. Rolling Process:
Just after aggregates have been accelerated, they are dry rolled with a roller weighing at least 10 tonnes.
In bitumen road ensures that the aggregates are compressed and connected appropriately.
4. Bitumen Application:
A homogenous coating of bitumen binder is sprayed on the dry-rolled compressed aggregates using a pressure distributor or motorized hand sprayer.
5. Key Aggregate Spreading:
Once the bitumen has been correctly spread, key aggregates are properly laid and the rolling process is resumed for proper compaction.
The cross profile is also assessed at the same time.
6. Seal Coat Application:
If the road is to be opened to traffic and the further surface course is not necessary, a seal coat is applied.
It might be comprised of sand and bitumen, or it could be surface dressing for road.
Verify the cross profile of the roadway with a pattern and the longitudinal profile with the road’s straight edge.
On a 3 m road, the maximum allowable undulation is 12 mm.
8. Open to Traffic:
The road is opened to traffic within 24 hours after its completion.
Advantages of Bitumen Road:
- Bituminous roads do not develop surface fissures.
- This road’s maintenance costs are likewise quite low.
- These roads are waterproof, non-slippery, smooth, and long-lasting, and they create a more comfortable road surface for vehicles.
- It can endure the damaging natural impacts of severe rain, excessive heat, and temperature changes.
Disadvantages of Bitumen Road:
- The viscosity of the bitumen and aggregate mix has a significant influence on the effectiveness of a bituminous road.
- When bituminous material is utilized in excess of the value for a certain mix, the efficiency of the bituminous road suffers.
- Impurities in bitumen can pollute soil and hence groundwater as it melts. These may contain trace levels of hydrocarbons.
- Aperture and drainage path clogging throughout construction and service life
- More salting is needed to prevent snow during the winter season.
Their major goal is to exchange academic information and expertise to ensure that bitumen is utilized in the most effective and efficient methods for its many applications in road operations.