CRUSHED ROCK AGGREGATES IN CONCRETE: INVESTIGATIONS AT THE BUILDING RESEARCH ESTABLISHMENT

Reference is made to the four characteristics which usually distinguish crushed rock aggregates from sands and gravels, and the influence these have on concrete is discussed. Information is provided on a co-operative research programme initiated in 1965 which consisted of two parts, (1) a survey of the grading of crushed rock fines obtained from quarries of the British Granite and Whinstone Federation, and the Limestone Federation, (2) an extensive laboratory investigation on concrete made with crushed rock aggregates, both fine and coarse, from selected quarries. References are given to the results of the grading survey, and a summary of the second part of the research programme is given in this paper. Details are provided on the aggregates used; treatment and characteristics; mixes and test procedures; concrete workability and crushing strength; the results of tests from the durability programme and observations on general performance. The results obtained from the research programme indicated that all the aggregates used produced concrete of satisfactory crushing strength and other mechanical properties. The various characteristics of the concrete such as strength, elastic modulus and drying shrinkage varied according to the aggregate used. However, there appeared to be no relationship between the performance of the concrete and the characteristics of the aggregate, except perhaps its absorption. It was considered that the high dust content of crushed rock fines compared with natural sands did not have serious adverse effect on the properties of the concrete, and should be regarded as part of the difference in grading characteristics of such materials. It was concluded from this investigation that the performance of concrete made with a particular aggregate cannot be assessed from standard tests on the aggregate. To assess its performance, concrete should be made with the aggregate, and its crushing strength, elastic modulus, drying shrinkage and absorption characteristics measured. /TRRL/

  • Availability:
  • Corporate Authors:

    Quarry Managers Journal Limited

    62-64 Baker Street
    London W1M 2BN,   England 
  • Authors:
    • TEYCHENNE, D C
  • Publication Date: 1978-5

Language

  • English

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 122-137
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00189543
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Apr 12 1979 12:00AM