What are the specs for runways at international airports? 1) What are the materials that international airport runways are made of? If runways consists of several layers, what are they made of, and what is their depth and other specifications?

2) What are the surface specifications/properties required of such runways?

3) What kind of routine maintenance drills do such runways require?
Runways for international airports are usually man made, which means that they are made up of asphalt or concrete and sometimes are a mixture of both. The depth for the runways are 29cm to 33cm.
Runways are usually around 150ft wide. For an international airport will have a runway around 6,000ft long, but depending on the size of the aircraft that land there a runway will need to be 8,000ft or more.
I found this link which should give you information on runway maintenance.