The authors review the results of four types of tests on plain and fibre-reinforced concrete, and the poor quantitative agreement between researchers and the influence of the piece size, test method and type of testing machine are noted. The additional, circumferentially notched round bar under bending (cnrbb) test is described in detail from which are calculated the critical stress intensity factor at the tip of crack when failure occurs and the critical strain energy release rate. Information is included on concrete mix proportions used for an investigation of concrete fracture toughness, with dimensions of specimens, details of steel and polypropylene fibres incorporated in the mix, and the testing arrangement which is illustrated. The schematic load-deflection curves for various mixes are shown and discussed. Photographs show specimens at point of fracture and the variation of the toughness parameters with specimen notch depth is discussed. It is concluded that the cnrbb test is an effective method for comparing the fracture toughness of plain and fibre reinforced concrete. (TRRL)

  • Availability:
  • Corporate Authors:

    Cement and Concrete Association

    Wexham Spring
    Slough SL3 6PL, Buckinghamshire,   England 

    Concrete Society

    Terminal House, Grosvenor Gardens
    London,   England 
  • Authors:
    • Javan, L
    • Dury, B L
  • Publication Date: 1979-12

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 31-3
  • Serial:
    • Volume: 13
    • Issue Number: 12
    • ISSN: 0010-5317

Subject/Index Terms

Filing Info

  • Accession Number: 00309784
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Aug 5 1980 12:00AM