AGGREGATE GRADING TO NZS 3104

The paper discusses an apparent anomaly in the standard suggesting possible alternatives. In order to meet the current specification for combined coarse aggregates a producer would need to achieve a maximum of about 35 per cent passing the 9.5 mm sieve. Using grading curves it would appear that an aggregate with 52 per cent passing the 9.5 mm sieve is required with a sand that all passes the 4.75 mm sieve. There is a very large local market for 14 mm maximum size concrete, however interpolation suggests that the grading of a suitable aggregate would be about 70 per cent passing the 9.5 mm sieve. The author claims that the need to comply with combined fractions requirements inhibits an engineer attempting to design to an ideal grading curve. It has been suggested that the standard does not apply to a 14 mm or a possible 18 mm maximum size. Some ammendments are outlined which would allow the producer to meet customers needs within good engineering practice and comply with local standards. (TRRL)

  • Availability:
  • Corporate Authors:

    Concrete Publications

    Private Bag
    Porirua,   New Zealand 
  • Authors:
    • RAMSEY, J
  • Publication Date: 1987-4

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00470091
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Jul 31 1988 12:00AM