The table below shows properties of three trial aggregate blends that are to be evaluated so as to determine their suitability for use in a Superpave mix. If the nominal maximum sieve of each aggregate blend is 19 mm, determine the initial trial asphalt content for each of the blends.

Question

What will be an ideal response?

Answer 1

Assume:

Pb = 0.05

Ps = 0.95

Gb = 1.02

Va = 0.04

Since Gsb and Gse are given, the trial percentage of asphalt binder can be found

using Equations 18.17, 18.18, and 18.19.

For trial blend 1:

Use Equation 18.18,



Use Equation 18.19,

Vbe = 0.176 – 0.0675 log Sn = 0.176 – 0.0675 log (19) = 0.0897



Use Equation 18.20,



For trial blend 2:

Use Equation 18.18,



Use Equation 18.19,

Vbe = 0.176 – 0.0675 log Sn = 0.176 – 0.0675 log (19) = 0.0897

Find Ws,



Use Equation 18.19,

Vbe = 0.176 – 0.0675 log Sn = 0.176 – 0.0675log (19) = 0.0897

Find Ws,