Generally, most regulations do not recommend using reclaimed asphalt or simply do not allow recycling old asphalt layers into SMA. However, some good test results do exist for SMA mixtures with reclaimed asphalt (Perez et al., 2004).
The requirements for reclaimed asphalt to be used for SMA according to the EN 13108-5 standard are discussed in Chapter 14.
5.5.1 Natural Asphalt
Some results of the use of natural asphalt as an additive to road binder manufactured in a refinery are cited in relevant literature (Hausler and Arand, undated; Radenberg, 1997). Natural asphalt is usually added to increase resistance to permanent deformation.
The requirements for natural asphalts have also been cited in the EN 13108-4 standard, Annex B.
