Practical recommendations are made for recycling asphalt pavements by (a) use of selected reclaiming agents to restore durability and consistency to the aged asphalt, and (b) application of a rational mix design.

Satisfactory reclaiming agents are characterized as (a) being fully compatible with the broadest range of aged asphalts, (b) providing durability to the aged asphalts, (c) being capable of producing a reclaimed asphalt within paving-grade consistency, and (d) assuring good wetting and thorough mixing. Interim specifications are proposed for reclaiming agents fulfilling these requirements.

The basic information needed for a rational design is discussed and identified as follows: (a) gradation of the aggregate in the salvaged pavement, (b) asphalt content of the old pavement, (c) consistency of the extracted asphalt, (d) asphalt demand of the aggregate, and (e) desired consistency of the asphalt in the recycled pavement.

A simple formula and two nomographs are presented as aids for the design engineer.