Aggregate, roads

The way in which aiteration develops can influence roadstone durability. Weathering may reduce the bonding strength between grains to such an extent that they are plucked out easily from the stone. Chemical alteration is not always detrimental to roadstone performance indeed a small amount of alteration may improve the resistance of a rock to polishing 

Rock type Water absorption Specific gravity Aggregate crushing value Aggregate impact value Aggregate abrasion value Polished stone value 

---

Ro 23-9424 Road aggregate Road ballast Road oil Road oils Roadstone Roadway surfaces Robemdine [25875-50-7]... 

The calcium sulfate [7778-18-9] discharged from the furnace can also be recovered. This is less the practice in the United States where natural gypsum is plentiful and inexpensive than in Europe, where CaSO recovery for use in cement (qv) and self-leveling floors is common. Some CaSO is recovered in the United States, primarily for lower end uses such as road aggregate. 

Bitumen additives to give wet adhesion to road aggregates Quaternary ammonium compounds Imidazoline derivatives Amine ethoxylates Wetting agents... 

As for other waste, the plan calls for glass to be crushed and used for road aggregate, metals to be sold or given away, and anything biodegradable to be composted for mulch. 

The Wettability of Road Aggregates with Doped Bituminous Binders... 

Figure 2.1 Sand equivalent values of sands from various rocks. (From Nikolaides A. and E. Manthos, Sand equivalent of road aggregates tested with European and American standards and methylene blue results. Proceedings of the 4th International Conference, Bituminous Mixtures and Pavements , Vol. I, p. 199. Thessaloniki, Greece Aristotle University, 2007.)...

Hosking R. 1992. Road Aggregates and Skidding. TRL, HMSO. London Transport Research Laboratory. 

The conservation of natural resources for road aggregate production, particularly of hard and durable aggregates for surfacing, is a serious matter particularly for countries that do not possess sufficient reserves of such materials. Even for countries that do possess sufficient reserves, the use of RA lengthens the exploitation period of the existing quarries and delays the opening of new ones in some cases, it is a difficult task because of the strict environmental rules imposed. 

Needless to say, for countries possessing no natural resources for road aggregate production, the use of RA is also beneficial since it reduces the cost of asphalts owing to the incorporation of less amount of expensive new aggregate in the mix. 

The cost of using a dust suppressant is very site-specific. Certain types of dust suppressants work better in certain types of road aggregate. Recommendations are ... 

When laterite is exposed to air or dried out (i.e. by lowering the ground water table) irreversible hardening often occurs, producing a material suitable for use as road aggregate (U.S. Army, 1997). 

Uses Wetting agent dispersant dewatering agent in eiec. components and road aggregates emuisifier for fats, waxes, min, oiis and metaiworking iubricants corrosion inhibitor... 

---