Rejuvenators

Rejuvenators are products designed to restore original properties to aged (oxidized) asphalt binders by restoring the original ratio of asphaltenes to maltenes. Many rejuvenators are proprietary, making it difficult to offer a good generic description. However, many rejuvenators contain maltenes because their quantity is reduced by oxidation. Rejuvenators will retard the loss of surface fines and reduce the formation of additional cracks, however they will also reduce pavement skid resistance for up to 1 year (Army and Air Force, 1988[1]). Because of this, rejuvenators are generally appropriate for low-volume, low-speed roads or parking lots. They have also been used on airport runways for small general aviation facilities.

Purpose

Preventive maintenance. Restore original properties to aged asphalt binder. Rejuvenators may be able to postpone the need for a BST for a year or two.


Materials

Various compounds. Most rejuvenators are proprietary and thus a general description of their constituent materials is not possible.

Mix Design

None beyond the manufacturer’s design. A test patch may be needed to determine effectiveness and the proper application rate.


Other Info

A rejuvenator should not be applied to a pavement having an excess of binder on the surface such as that found in slurry seal, OGFC, or BSTs. When excessive binder is on the surface, the rejuvenator will soften the binder and cause the surface to become tacky and slick (Army and Air Force, 1988[1]).

The amount of air voids in the HMA being rejuvenated should be at least 5 percent to ensure proper penetration of the rejuvenator into the pavement. If the voids are less than 5 percent, the rejuvenator may fill the voids and thus cause an unstable mix (Army and Air Force, 1988[1]).

Rejuvenators should be applied in hot weather, above 20°C (70°F), so that the rejuvenator (1) will penetrate more deeply into the asphalt pavement and (2) will cure sooner (Army and Air Force, 1988[1]).




Footnotes    (↵ returns to text)
  1. Departments of the Army and the Air Force (Army and Air Force).  (August 1988).  Standard Practice for Pavement Recycling.  Army TM 5-822-10, Air Force AFM 88-6, Chapter 6.