Superpave Gradation Requirements

Superpave mix design specifies aggregate gradation control points through which aggregate gradations must pass. These control points are very general and are a starting point for a job mix formula.

These tables (data taken from AASHTO MP 2, Standard Specification for Superpave Volumetric Mix Design) show typical Superpave aggregate specifications for 37.5 mm (1.5 inch) down to 9.5 mm (0.375 inch) nominal aggregate sizes.  Significant figures are the same as those in AASHTO MP 2.

Table 1. 37.5 mm (1.5 inch) Nominal Size
Sieve Size Control Points Restricted Zone
(mm) (U.S.) Lower Upper Lower Upper
50 2 inch 100
37.5 1.5 inch 90 100
25 1 inch 90
19 3/4 inch
12.5 1/2 inch
9.5 3/8 inch
4.75 No. 4 34.7 34.7
2.36 No. 8 15 41 23.3 27.3
1.18 No. 16 15.5 21.5
0.60 No. 30 11.7 15.7
0.30 No. 50 10.0 10.0
0.15 No. 100
0.075 No. 200 0 6

 

Table 2. 25 mm (1 inch) Nominal Size
Sieve Size Control Points Restricted Zone
(mm) (U.S.) Lower Upper Lower Upper
37.5 1.5 inch 100
25 1 inch 90 100
19 3/4 inch 90
12.5 1/2 inch
9.5 3/8 inch
4.75 No. 4 39.5 39.5
2.36 No. 8 19 45 26.8 30.8
1.18 No. 16 18.1 24.1
0.60 No. 30 13.6 17.6
0.30 No. 50 11.4 11.4
0.15 No. 100
0.075 No. 200 1 7

 

Table 3. 19 mm (3/4 inch) Nominal Size
Sieve Size Control Points Restricted Zone
(mm) (U.S.) Lower Upper Lower Upper
25 1 inch 100
19 3/4 inch 90 100
12.5 1/2 inch 90
9.5 3/8 inch
4.75 No. 4
2.36 No. 8 23 49 34.6 34.6
1.18 No. 16 22.3 28.3
0.60 No. 30 16.7 20.7
0.30 No. 50 13.7 13.7
0.15 No. 100
0.075 No. 200 2 8

 

Table 4. 12.5 mm (1/2 inch) Nominal Size
Sieve Size Control Points Restricted Zone
(mm) (U.S.) Lower Upper Lower Upper
19 3/4 inch 100
12.5 1/2 inch 90 100
9.5 3/8 inch 90
4.75 No. 4
2.36 No. 8 28 58 39.1 39.1
1.18 No. 16 25.6 31.6
0.60 No. 30 19.1 23.1
0.30 No. 50 15.5 15.5
0.15 No. 100
0.075 No. 200 2 10

 

Table 5. 9.5 mm (3/8 inch) Nominal Size
Sieve Size Control Points Restricted Zone
(mm) (U.S.) Lower Upper Lower Upper
12.5 1/2 inch 100
9.5 3/8 inch 90 100
4.75 No. 4 90
2.36 No. 8 32 67 47.2 47.2
1.18 No. 16 31.6 37.6
0.60 No. 30 23.5 27.5
0.30 No. 50 18.7 18.7
0.15 No. 100
0.075 No. 200 2 10