Consulting civil engineer, Oakland, Calif.
Vice president, Arizona Refining Co., Phoenix, Ariz.
Pages: 17 Published: Jan 1980
A newly developed asphalt-rubber material with unique adhesive and rheological properties has made it possible to form highly elastic single surface treatments with a multilayered aggregate structure. Conventional asphalt distributor trucks are used to apply a heavy spread of the hot asphalt-rubber material on a prepared surface followed by the immediate embedment of aggregate chips into this cast-in-place membrane by conventional chip spreading and rolling equipment and procedures. A sufficient quantity of aggregate chips must be applied both to build up the multilayered aggregate structure and to provide a skid-resistant pavement surface. The composition and properties of the asphalt-rubber material are described together with procedures for constructing the surface treatment. Audit results are presented from an experimental field installation of a multilayered single surface treatment consisting of four test sections, where the rates of application of the asphalt-rubber membrane material ranged from 1.86 to 8.87 hot litre/m2 (0.41 to 1.96 hot gal/yd2) with corresponding aggregate retention rates of 13 to 37 kg/m2 (24 to 68 lb/yd2). Based on these audit results and experience gained from the observed performance of other field installations, a nomograph for designing such multilayered aggregate single-surface treatments has been formulated and is presented. The nomograph can be used to determine the rates of application of asphalt-rubber material and aggregate chips to obtain a desired thickness of surface treatment or, alternatively, to determine the spread rate of aggregate chips and thickness of the surface treatment for a specific rate of asphalt-rubber membrane application.
surface treatment, stress-absorbing membrane, asphalt-rubber, asphalt, design, performance
Paper ID: STP38363S