A statistical quality control specification (details are provided in an attachment) is described which allows acceptance or rejection of material on the average of test results in lieu of accepting or rejecting on an individual basis. A randomized method is used to determine when and where to sample (the concept is described in an attachment). The details are given of key points in the specification. These include detail requirements of aggregate subbase and base materials (liquid limit and plasticity index); job mix formula; plant inspection acceptance; adjustment system; and the referee system (to allow for resampling and testing when there is doubt that the test results are valid). The review of pilot projects indicate that desired results were being achieved. To establish the bases for a quality assurance system in the aggregate industry, data is assembled from a given plant and fed into computers to establish production control records. If the records reach a given level of confidence, the plant is rated as a Level I Produce. A Level I Producer can ship aggregate on certification with only random spot checking by State Inspectors. All other producers will have their production controlled by the pre-sampling and pretesting method.

  • Supplemental Notes:
    • Proceedings from a conference on Utilization of Graded Aggregate Base Materials in Flexible Pavements, March 25-26, 1974, Oak Brook Hyatt House, Oak Brook, Illinois.
  • Corporate Authors:

    National Crushed Stone Association

    1415 Elliot Place, NW
    Washington, DC  United States  20007

    National Sand and Gravel Association

    900 Spring Street
    Silver Spring, MD  United States  20910

    National Slag Association

    300 South Washington Street
    Alexandria, VA  United States  22314
  • Authors:
    • Fielding, R V
  • Publication Date: 1974

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00127538
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 7 1976 12:00AM