4126Aggregate for Polymer-Modified Microsurfacing

4126.01DESCRIPTION

Crushed stone. For non-Interstate mixes steel slag may also be used.

4126.02GRADATION

For quartzite, granite, and slag meet requirements for Gradation No. 37 of the Aggregate Gradation Table, Article 4109.02. For limestone and dolomite meet requirements for Gradation No. 38 of the Aggregate Gradation Table, Article 4109.02

4126.03QUALITY

Meet requirements of Table 4126.03-1 and 4126.03-2 with the exception that use of Friction Type 2 crushed stone requires a maximum abrasion loss of 30% and sand

Aggregate for Flexible Paving Mixtures

4127.02

equivalence of not less than 60. Testing is based on aggregate crushed to 3/4 inch nominal size.

Aggregate Quality

Table 4126.03-1: Aggregate Quality Maximum Percent Test Method Allowed

Abrasion

AASHTO T 96

A Freeze

Office of Materials Test Method No. Iowa 211, Method A

Alumina(a, b)

0.7

Office of Materials Test Method No. Iowa 222

Sand Equivalence

45 (Minimum)

Organic Materials

0.01

(a)

(b)

AASHTO T 176 Office of Materials Test Method No. Iowa 215

If the Alumina value passes, the A-Freeze is not needed for specification compliance. If the Alumina value fails, determine the A Freeze value for specification compliance. Alumina does not apply to gravel.

Table 4126.03-02: Maximum Permissible Amounts of Objectionable Material Maximum Objectionable Materials Test Method Percent Allowed Unsound chert particles retained on No. 4 sieve

0.5

Materials I.M. 372

Total of all unsound chert, shale, coal, and iron combined

1.0

Materials I.M. 372

Clay Lumps/Friable Particles

0.5

Materials I.M. 368

Organic Materials, except coal

0.1

Iowa DOT Materials Laboratory Test Method No. 215