Erosion Stone Sections 4130.03-4130.05 specifications.pdf

This specification document outlines the technical requirements for erosion stone materials as established by the Iowa Department of Transportation (Iowa DOT). Erosion stone consists of broken limestone, dolomite, quartzite, granite, or broken concrete with steel removed, with a nominal 6-inch size specification requiring 100% of material to pass a 9-inch screen and 100% to be retained on a 3-inch screen. The Iowa DOT Engineer will determine gradation compliance through visual inspection prior to loading and may designate material as too fine or too coarse based on this assessment.

For quality requirements, erosion stone materials—except recycled concrete—must meet specific performance standards established in Table 4130.05-1, including a maximum 15% freeze loss per Iowa DOT Materials Laboratory Test Method No. 211 (Method C), a maximum 50% abrasion loss per AASHTO T 96, and a maximum 5% clay lumps and friable particles per Materials I.M. 368. All quality testing must be performed on product crushed to a maximum size of 3/4 inch or 1 inch. Recycled concrete used as erosion stone is exempt from these quality requirements, providing an alternative material option for suppliers.