Reclaimed asphalt pavement

Although the majority of old asphalt pavements are recycled at central processing plants, asphalt pavements may be pulverized in place and incorpo- 

Rehable figures for the generation of RAP are not readily available fi om all state highway agencies or local jurisdictions. Based on incomplete data, it is estimated that as much as 41 million metric tons (45 million tons) of RAP may be produced each year in the United States [153-158]. 

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Brantley AS, Townsend TG (1999) Leaching of pollutants from reclaimed asphalt pavement. Environ EngSci 16 105-116... 

The use of plant-recycled hot-mixed asphalt (HMA) for public road pavement in Japan first began in 1975. The Japan Road Association promoted the technology for plant-recycled HMA pavement in Japan with its 1984 publication of The Plant-Recycled HMA Pavement Technical Guideline, and since 1985, positive efforts have been made to reuse more reclaimed asphalt pavement (RAP). 

Norin, M. and Stromvall, A. M., Leaching of organic contaminants from storage of reclaimed asphalt pavement, Environ. Technol, 25, 323-340, 2004. 

Coal bottom ash/ boiler slag BA/BS 53.5 million t (59.4 million T) 15 Reclaimed asphalt pavement RAP NR... 

The particle size distribution of milled or crushed RAP may vary to some extent depending on the type of equipment used to produce the RAP, the type of aggregate in the pavement, and whether any imderlying base or sub-base aggregate has been mixed in with the reclaimed asphalt pavement material during the pavement removal. 

Granular base Blast furnace slag Coal boiler slag Mineral processing wastes Municipal solid waste combustor ash Nonferrous slags Reclaimed asphalt pavement Contaminated soils Reclaimed concrete Steel slag Waste glass... 

Embankment or fill Coal fly ash Mineral processing wastes Nonferrons slags Reclaimed asphalt pavement Reclaimed concrete Scrap tires... 

Recycled AC is allowed to be used in all pavement layers except runway surface course. The recycled AC, consisting of reclaimed asphalt pavement (RAP), coarse aggregate, fine aggregate, mineral filler and asphalt cement, should meet the requirements set for an AC (see Tables 5.16 and 5.17). However, the amount of RAP to be incorporated in the mix is limited to 30%. 

Austerman A.J., WS. Mogawei and R. Bonaquist. 2009. Investigation of the influence of warm mix asphalt additive dose on the workability, cracking susceptihility, and moisture susceptihility of asphalt mixtures containing reclaimed asphalt pavement. Proceedings of 54th Annual Conference of the Canadian Technical Asphalt Association. Laval, Quebec, Canada Polyscience Publications Inc. 

The decision to choose the most suitable asphalt plant is quite complicated. It is influenced by the market conditions related to demand and selling price of the asphalt, the typical hourly output capacity, the cost of purchasing the plant, the types of asphalt usually required to be produced, the capability of the plant to produce recycled asphalt, the amount of reclaimed asphalt (or reclaimed asphalt pavement [RAP]) to be used, the land space availability and the environmental restrictions (mainly emissions and noise). 

Prior testing calibration is needed, either on the complete mixture or on its components, aggregate and reclaimed asphalt pavement. The calibration procedure is described in the relevant standard. 

The material removed from the asphalt layers to be re-used, hence recycled, containing bitumen and aggregates, is called reclaimed asphalt (RA), under European Union terminology, or reclaimed asphalt pavement (RAP), under US terminology. 

Austroads. 2013. Maximising the Re-Use of Reclaimed Asphalt Pavement Binder Blend Characterization. AP-T245-13. Sydney, Australia Austroads. 

McDaniel R., H. Soleymani, and R.M. Anderson. 2001. Recommended Use of Reclaimed Asphalt Pavement in the Superpave Mix Design Method Guidelines. Research Results Digest 253. Washington, DC Transportation Research Board. 

Stroup-Gardiner M. and T. Wattenberg-Komas. 2013. Recycled Materials and Byproducts in Highway Applications Volume 6 Reclaimed Asphalt Pavement, Recycled Concrete Aggregate, and Construction Demolition Waste. NCHRP Synthesis 435. Washington, DC TRB, National Academy of Science. 

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