Bitumen is also called as Tar and is available in defferent grades. like 60/70 and 80/100 .Bitumen 60/70 melt only in heigh temperature but 80/100 easly start melting like normal temperature sunlight about 40 degree. So 80/100 bitumen is used for the base macadom or bottom layer of the bitumen pavement normally having thickness 50mm and 60/70 bitumen used for top layer of the bitumen pavement about 30mm thick in order to avoid melting of the bitumen which leeds the surface of the road very smooth and their by avoiding accidents especially in rainy or mist falling area.
Bitumen is also called as Tar and is available in defferent grades. like 60/70 and 80/100 .Bitumen 60/70 melt only in heigh temperature but 80/100 easly start melting like normal temperature sunlight about 40 degree. So 80/100 bitumen is used for the base macadom or bottom layer of the bitumen pavement normally having thickness 50mm and 60/70 bitumen used for top layer of the bitumen pavement about 30mm thick in order to avoid melting of the bitumen which leeds the surface of the road very smooth and their by avoiding accidents especially in rainy or mist falling area.
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