Section 4118.  Bedding Material for Non-Primary Road Projects

 

4118.01     DESCRIPTION.

Aggregate of the following types:

·         Crushed Stone,

·         Gravels for which 75% or more of the particles retained on the 3/8 inch sieve have at least one fractured face as defined in Materials I.M. 305 (the fractured face requirement shall only apply to bedding material placed under Primary or Interstate roadways), or

·         Crushed PCC, if approved by the Engineer.

 

4118.02     GRADATION.

Meet the requirements for Gradation No. 3 of the Aggregate Gradation Table, Article 4109.02. Restrictions on the No. 200 sieve do not apply.

 

4118.03     QUALITY.

The requirements of Table 4118.03-1 apply to individual virgin aggregates:

 

Table 4118.03-1: Coarse Aggregate Quality (Virgin Material)

Coarse Aggregate Quality

Maximum Percent Allowed

Test Method

Abrasion

50

AASHTO T 96

C – Freeze (a)

20

Iowa DOT Materials Laboratory Test Method No. 211, Method C

A – Freeze (a)

6

Iowa DOT Materials Laboratory Test Method No. 211, Method A

Alumina (a)

0.5

Iowa DOT Materials Laboratory Test Method No. 222

(a) Meet at least one of the C – Freeze, A – Freeze, or Alumina requirements.

 

For crushed PCC, meet requirements of Materials I.M. 210.