4122.01DESCRIPTION
Crushed stone meeting the following requirements.
4123.03
Modified Subbase Material
4122.02
GRADATION.
A.
Produce Macadam Crushed Stone with a nominal maximum size of 3 inches. Screen over a 3/4 inch screen, or when specified in the contract documents, a 1 inch screen. This is identified as Gradation No. 13 of the Aggregate Gradation Table, Article 4109.02.
B.
The aggregate passing the 3/4 inch or 1 inch screen may be furnished as the Choke Stone material; however, 6% to 16% of the material shall pass the No. 200 sieve. This is identified as Gradation No. 13b of the Aggregate Gradation Table, Article 4109.02.
4122.03QUALITY
For Macadam Stone Base and Choke Stone, meet the requirements of Table
Table 4122.03-1: Crushed Stone Base Quality Macadam Quality
Maximum Percent Allowed
Test Method
Abrasion
50
AASHTO T 96
C Freeze
Iowa DOT Materials Laboratory Test Method No. 211, Method C
Get an email when 4122 changes
Iowa revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.