Crumb rubber is mainly obtained from the recycling process of waste tires. This rubber modified asphalt that has been modified chemically. Its rheological properties are known to improve at high and low temperatures thereby providing a longer life as compared to the conventional asphalt.
It is more expensive than the regular asphalt, but it has many advantages over it. Studies that have been conducted have revealed that it is effective in overcoming some of the major problems experienced with the regular rubber asphalt. Again, rubber crumb has improved properties that make it ideal for road construction. Its pieces are blended with hot paving asphalt cement.
The blend produced is widely used in pavement. Recycle tires constitute about 25% of the binder. This binder is very flexible and tougher. The tire is also helpful in increasing the viscosity of the binder as well as improving the pavement’s resistance against cracking. It is also highly resistant to weathering and oxidation.
Types of crumb rubber
It is made of finely grounded rubber. The composition of crumb rubber modifier in the terminal blend is about 15-20 %. The mixing process is done at the refinery. For consistency, liquid asphalt which has been modified is mixed with crumb rubber. You can also mix it with coarse aggregate. Grinding rubber finely is helpful in reducing the amount of rubber used as well as increasing the efficiency of the mixing process.
This is another version of crumb rubber that consists of paving grade asphalt, vulcanized rubber, and other additives. It is produced by mixing rubber with asphalt cement. Unlike with the terminal blend, here the mixing process is done on the site.
Advantages of crumb rubber
It has been proven to be more durable as compared to the regular asphalt concrete since it is highly resistant to cracking. It can, therefore, last for longer than the conventional asphalt. You can use it to extend the life of your roadway. In addition to this, it is known for resisting softening and brittleness that is very common with the typical asphalt concrete.
Its maintenance cost is very low because it is highly resistant to cracking. It is resistant to weathering and oxidation making it less brittle. You can save up to 50 % of the overall cost by using crumb rubber.
It can maintain its dark for long as compared to the standard overlays. Additionally, it has a high resistance to weathering, and it is capable of absorbing noise thereby reducing noise on the road.