Section 4132. Special Backfill Material.

4132.01 DESCRIPTION.

4132.02 GRADATION.
Meet the following gradations:

TABLE 4132.02 - 1
Material Gradation (Aggregate Gradation Table,
Article 4109.02)
Crushed Stone
Crushed PCC
Crushed Composite Pavement
#30
Gravel or Gravel Blends with Crushed Stone, PCC or Composite #31

TABLE 4132.02 - 2
Material Gradation
Reclaimed HMA Nominal top size of 2 inches (50 mm)

4132.03 QUALITY.
For gravel mixture do not exceed the following:

TABLE 4132.03

Maximum Permissible Amounts of Objectionable Materials Maximum Percent Allowed Test Method
Plasticity Index 10 Iowa DOT Materials Laboratory Test Method 109
Carbon 1.0 Iowa DOT Materials Laboratory Test Method 111