| 摘要 |
Filler and heated aggregate are mixed in a first stage with a partial amount of bitumen heated into liquid state, whereupon the mixture is allowed to cool to ambient temperature. After cooling the mixture appears as a granular semifinished product which, in a second stage, is mixed with the remaining amount of heated liquid bitumen. Upon cooling the mixture appears as a granular mastic asphalt. Only a partial amount of the total amount of filler material to be contained in the end product is added in the first mixing stage, the remaining amount of bitumen being mixed with remaining amount of filler to form a suspension which is mixed with the semifinished product in said second stage. The semifinished product is comprised of 90 - 95 % by weight of aggregate, 2 - 5 % by weight of filler and 2 - 4 % by weight of bitumen. |
