2400 W. Oxford Ave.
Englewood, CO 80110

303-762-1160

Specifications

Class 6 Base Course – April 2026

AASHTO T 27, Sieve Analysis of Fine and Course Aggregates

Sieve Size % Passing CDOT Grading Specifications
% Passing
25.4 mm (1″) 100
19.0 mm (3/4″) 99 100
12.5 mm (1/2″) 87 –
9.5 mm (3/8″) 77 –
4.75 mm (No. 4) 59 30-65
2.36 mm (No. 8) 49 25-55
1.18 mm (No. 16) 37 –
600 um (No. 30) 26 –
300 um (No. 50) 17 –
150 um (No. 100) 11 –
75 um (No.200) 9 3-12
R-Value 83

AASHTO T 96, Resistance to Degradation of Small Size Coarse
Aggregate by Abrasion and Impact

Sample ID Grading Weight Before (g) Weight After (g) % Loss
Class 6 D 5000.0 2915 42

AASHTO T 89, Determining the Liquid Limits of Soils

Sample ID Liquid Limit
Class 6 NL

AASHTO T 90, Determining the Plastic Limits and Plasticity Index of Soils

Sample ID Plastic Limit Plasticity Index
Class 6 NL NP

AASHTO T 180, Moisture-Density Relations of Soils

Sample ID Maximum Density (Proctor), pcf Optimum Moisture %
Class 6 118.6 12.1

1 1/2″ Dry Screened Rock

Sample 1 1/2 in 1 in 3/4 in 1/2 in 3/8 in No. 4
1 1/2 in 100 66 29 3 2 1

Recycled Asphalt

Sieve Size % Passing
1 1/2″ 100
1″ 100
3/4″ 100
1/2″ 97
3/8″ 93
No. 4 80
No. 8 67
No. 16 51
No. 30 38
No. 50 27
No. 100
 18
No. 200 13.1
AC Content %* 5.00

* Asphalt cement content does not reflect an ash correction or a retention factor.