Asphalt (paving)
Asphalt ist a mix of bitumen, aggregate and additives. Usual asphalt consists to 90 to 95 percent by weight of aggregate and 5 to 10 % of bitumen.
Properties
Asphalt is water repellant due to the bitumen which is part of the asphalt conglomerate.
The physical properties are dependent on the temperature of the material, as at high temperatures, asphalt has a very distinctive viscous behaviour, which becomes more and more elastic with dropping temperatures.
As the physical properties are mainly dependent on the used aggregates, they can vary in a large range. Typical values are:
- heat conductivity: 0.8 - 1.2 W/mK
- specific heat capacity: 850 - 1050 J/kgK
Usage
The main use of asphalt is the creation of pavements like roads or airfields. Due to it's physical properties, it can be used as a robust basement as well as a high-load surface.