STATE OF OHIO

DEPARTMENT OF TRANSPORTATION

SUPPLEMENT 1071

QUALITY CONTROL REQUIREMENTS FOR STEEL SLAG AGGREGATE PRODUCER/PROCESSORS

August 28, 2007April 19, 2002April 18, 2008

1071.01Background

1071.02Scope

1071.03Steel Slag Quality Control Plan

1071.04Quality Control Requirements for Steel Slag Producers/Processors

1071.05Test Methods

1071.01 Background. Steel slag aggregates are recognized to provide a durable skid resistant asphalt pavement. However, unique circumstances in steel slag production as a byproduct of steel making and subsequent byproduct stockpiling necessitates unique requirements on the producers and processors of steel slag as a material for use in asphalt concrete pavements. The steel slag byproduct retrieved by a steel slag processor may come readily from the steel slag production process or come from older byproduct stockpiles or pits. These requirements assure necessitate the Department of pay proper attention to these unique variables and ensure that quality steel slag aggregate is used in Ohio’s pavements.

1071.02 Scope. The steel slag processor is responsible for processing raw slag into aggregate sizes complying with the applicable specification. Achieving quality steel slag aggregate for use in hot mix asphalt requires consistent application of steel slag producer and processor quality control. The quality control must start from the steel making process and continue through the processing of steel slag into an asphalt concrete pavement. These requirements cover the quality control plans of producers of steel slag and/or processors of steel slag and are required prior to shipment of any steel slag to Department projects.

1071.03 Steel Slag Quality Control Plan. The processor of steel slag is required to submit to the Laboratory for approval a Steel Slag Quality Control Plan that, at a minimum, covers the requirements in this specification. Additions to the plan beyond these requirements are at the processors discretion. This plan is necessary for the direct supplier of steel slag aggregate. When a steel slag processor submits a plan, the plan must include the quality control plan of the steel slag producer if material is retrieved from readily produced steel slag from the steel slag producer. The plan must be updated and submitted for approval every two years or earlier if any item of the plan has been modified. The plan shall designate two individuals (and include phone numbers) who are responsible for carrying out the details of the plan and who have authority to make process changes or cease steel slag processing if problems are seen.

1071.04 Quality Control Requirements for Steel Slag Producers/Processors. The following items are required as a part of the processor quality control plan. The producer quality control is required when steel slag is readily retrieved by the processor from the producer steel slag production process.

1071.041 Producer Quality Control. The producer quality control shall include the following:

  1. Designation of those responsible for carrying out the quality control at the steel making facility.
  2. Designation of separate quality control for each furnace (BOF, EAF, etc) at the facility.
  3. Method of handling (such as material pile separation, handling etc.) extreme variations in steel slag makeup due to major changes in practice (furnace operation).
  4. Change in practice (furnace operation) of steel slag quality control responses to the processor.
  5. Location of all quality control documentation.

1071.042 Processor Quality Control. The processor quality control plan shall include the following:

  1. Documentation of producer quality control for steel slag being processed but not originating from older byproduct stockpiles.
  2. Designation of older byproduct stockpiles from which steel slag is recovered with site maps.
  3. Rejection/selection process for suitable steel slag.
  4. Designation of all rejected/selected steel slag stockpiles with site maps. Disposal method and location of rejected stockpiles.
  5. Initial processing method when steel slag is removed from older byproduct stockpiles for removal of metallics, etc.
  6. Steel slag aggregate processing and testing (including testing frequency) verifying actual steel slag quality.
  7. Final processing method including equipment type, plant layout, storage sites or any other items pertaining to the operation.
  8. Product verification testing (including testing frequency) for gradations, absorption, percent soft pieces including lime agglomerations and other suitable steel slag quality testing at the processors discretion during final processing.
  9. Reprocessing procedure for failing material with retests and location of failed stockpiles.
  10. Site plan of processed stockpiles by size.
  11. Minimum one month aging at moisture content greater than aggregate absorption. If, after aging, fine aggregate has crusted or other tests show a problem for coarse or fine aggregate, reprocessing or screening is required.
  1. Moisture test prior to shipping according to customer requirements and documented on shipping records.
  2. Location of all quality control documentation.

1071.05 Test Methods. The following test methodsfrequencies are considered acceptable for required or optional testing of steel slag aggregate:

Method / Frequency
Deleterious substances (703.05 using hand crushing for soft pieces); Supplement 1029 / Every 2000 tons minimum
Gradation; ASTM C 136 / Every 2000 tons minimum
Absorption; Supplement 1031 / Every 2000 tons minimum
Loss by washing, ASTM C 117 / 1 per week minimum
Autoclave disruption, on file at the Laboratory / Optional
Expansion test (percent maximum at 7 days), on file at the Laboratory / Optional, using ASTM D 4792 on fine aggregate, 1.5 percent expansion as guide limit