| 摘要 |
The recycling material consists of broken-up, disintegrated or milled asphalt-concrete. The bitumen-quality and quantity of the old asphalt-concrete is determined before or after breaking up, disintegration or milling. The fresh material required for the conversion of the asphalt-concrete recycling material into melted asphalt is estimated from the findings above and opt. from the proportions and physical condition of the mineral constituents of the asphalt-concrete. The asphalt-concrete recycling material is comminuted to grain-size 0.2-100 (10-40) mm and then heated to about 200 deg.C. At first, the fresh material contg. only the amt. of gravel, sand and filler in the amt. determined for building up the melted asphalt, is heated to 200-250 deg.C. The recycling material and the fresh material contg. only the mineral constituents are mixed at this temp. The mixt. is then treated, at the given temp., with enough bitumen having given properties, to form a melted asphalt contg. 6.5-8 wt.% bitumen: The bitumen of the melted asphalt, formed of bitumen from the aspha-concrete and fresh bitumen, has penetration max. 70 (35-68) and softening pt. max. 60 (49-54). |
