Bitumen PG or Bitumen Performance grade:
Bitumen is known as the most important component of road pavement and asphalt, and if this bitumen does not have proper quality and performance, it will have a direct effect on the quality of asphalt. Recently, instead of producing viscosity-grade bitumen and penetration-grade bitumen, bitumen PG is used in asphalt production.
In bitumen PG, its functional characteristics have different characteristics against cracking and deformation due to cold and heat, and fatigue and predicting the hardening of the bitumen at the production site and in the factory, It is taken into consideration when preparing asphalt. Also, in bitumen PG, the amount of traffic and the passage of time, and the speed of loading on the road are considered.
What is Performance Grade Bitumen?
Overall, Performance Grade Bitumen or bitumen PG is graded based on its performance which is indicated in different temperatures.
For example, according to bitumen PG’s performance in cold or hot temperatures, they are classified that are called performance grade bitumen or bitumen PG.
Grading asphalt binder using the bitumen PG and selecting it is to make sure that the binder has got suitable properties needed for the environmental situation in, which it’s going to be used.
Difference between bitumen PG and other bitumens:
The difference between bitumen PG and other bitumens is in the actual conditions used in it so that for the optimal use of bitumen, different atmospheric conditions are taken into account, and especially the environmental climate is special.
the grading of road construction bitumen is based on the prediction of its performance on the road, so it is classified into different groups based on the properties of the bitumen in real conditions, such as types of weather, which are based on the precise behavior of its functional properties.
For example, the degree of penetration and the viscosity value of the penetration and plasticity tests do not affect the performance of bitumen, while in functional bitumen (PG), the physical properties of engineering principles are directly related to the performance of bitumen and the test It is done at a standard and specific temperature.
Classifition of bitumen PG:
bitumen PG is graded based on performance at different temperatures so that the highest and lowest asphalt temperatures are already calculated and the best bitumen at that temperature is suggested.
In this method, bitumen is classified based on performance characteristics in different weather conditions so that it can limit the permanent change of bitumen and its failure due to fatigue and cracking at low temperatures. For example, it is designed for bitumen in average weather conditions for seven consecutive days from 52 degrees Celsius above zero to 40 degrees Celsius below zero, it can be used at this temperature. In this category, any type of bitumen with two positive numbers A negative number is defined as which a positive number corresponds to the average of seven consecutive days of the highest pavement temperature in the summer season and a negative number is the minimum pavement temperature in seven consecutive days of the winter season.
Also, the Classification of bitumen PG is shown below
Applications of Bitumen PG:
1- PG52-28 is used for paving, construction, road care, and also in dense-graded and open-graded Hot Mix Asphalt (HMA). This product could be used for sealing cracks in paving and the edges.
PG52-28 is used for spraying in places like bridge decks and pavement protective membranes with fabrics too.
2- Also,PG58-22 is used in paving for both dense-graded and open-graded Hot Mix Asphalt (HMA) and in road construction, spraying and crack sealing applications.
3- PG58-28 is for paving dense-graded and open-graded Hot Mix Asphalt (HMA) and also in road construction, spraying, and crack sealing applications. This grade is widely used in very cold regions.
4- PG58-34 is suitable for higher-elevation roadways. This grade is a paving asphalt cement used for Hot Mix Asphalt production (HMA). It is also used for the edge of paving sealing and crack sealing.
5- PG58-40 is used for high-elevation locations. This grade of bitumen PG is paving asphalt for Hot Mix Asphalt (HMA) production . It could be used for sealing purposes and crack treating as well.
6- PG64-22 is suitable for paving for both new construction and pavement treatment projects and in dense-graded and open-graded Hot Mix Asphalt (HMA) and others. It can be used for sealing purposes and crack treating too.
7- PG64-28 is used for road construction, new paving, and pave care projects, in dense-graded and open-graded HMA. Others use for spraying applications, bridge decks, and pavement protective layers with fabrics. PG64-28 is used for the locations with low elevation too.
8- PG70-22 is used for areas with high traffic volume and for paving asphalt cement used for Hot Mix Asphalt (HMA) production.
Application of bitumen PG based on their Classification:
Best resistance in thermal cracking
- PG 64 -22
- PG 76 -22
- PG 64 -28
- PG 58 -34
Best resistance against rutting
- PG 82 -22
- PG 76 -28
- PG 70 -28
- PG 76 -22
Best for toll roads (High Volume)
- PG 64-22
Best for toll booths (high volume and slow traffic)
- PG 70-22
Best for rest area (high volume and standing traffic)
- PG 76-22