The Effect of Compaction Temperatures and Numbers on the Air Void Level of Porous Asphalt Pavements

Porous asphalt pavement is defined as an asphalt concrete that is designed with open gradation aggregate which helps in removing the water with an air void content of about 20% by creating drainage channels. Open gradation consists of large amounts of coarse aggregates and small amounts of fine aggregates. The water is drained due to this hollow structure, this air void content in the porous asphalt mixture which inevitably decreases with time is the main parameter affecting the service life as well as the structural and functional performance. Moreover, the reduction in air void content is one of the main reasons for the loss of permeability in porous asphalt pavements and this lead to the increase in pavement density under heavy traffic conditions. Each country has its own technical asphalt specification involving the required compaction energy and temperature. This study involves the effect of compaction temperatures and numbers on the air void in porous asphalt pavements prepared with 50/70 penetration grade bitumen. As a result of experimental studies, it has been observed that the reduced compaction temperature and the number of compaction (energy) increase the air void level in porous asphalt pavements.