Page 165 - RoadCem Manual - PCT BV

HOT ROLLED ASPHALT & PRECOATS
Figure 5.59 Sieve analysis
Figure 5.60 Texture of asphalt
This is the premium highway surfacing material that is used for many years and is responsible for a large percentage of the highway network being in such relatively good condition, even if it is covered by a surface dressing. The 35%/14mm HRA/WC is laid 50mm thick and not only provides a surface with good texture and a high PSV aggregate, it also imparts considerable strength to the existing pavement when applied as an overlay. It allows a low PSV (45 mm.) aggregate to be used in the matrix with the scarce and expensive high PSV aggregate only being used for the precoats. It is a very important factor when high quality, high PSV aggregate sources are becoming increasingly scarce.
The strength of the material is from the stiff (50.pen) binder, limestone filler, and sand matrix. There is no aggregate interlock to distribute load in the 30% and 35% aggregate content wearing courses
Figure 5.61 construction of asphalt
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