The aim of the investigation was to simulate and measure curing conditions as they exist on construction sites (many of the smaller contracts, some only during the early stage of their life, have no electricity supply), and to assess the effect of these non-standard conditions on the resulting strength of the concrete test samples. The curing conditions on site are described and the nature of the investigation then explained. This involved the assessment of cold water curing in which five concrete mixes of varying proportions to give a spread of 28-day strengths were made under laboratory conditions with local aggregates and ordinary portland cement. Twelve cubes were made from each mix, and the curing and testing procedures are discussed. Similar procedures were adopted with 18 cubes from each mix to assess the effect of drying out. The test results at 7-days and 28-days are presented, together with relevant temperature and humidity records. It was concluded that curing in unheated water on site for periods of up to 7 days has little effect on the 28-day strength. It is suggested that if the temperature of the unheated water is on average much less than that specified for controlled curing, that the 7-day results will be affected and any criteria used for assessing the 28-day results on the basis of the 7-day values will need to be modified. The provision of some form of curing tank is considered essential so that the curing conditions specified in BS1881 can be fulfilled. The author considers that the probable reduction in compressive strength at 28 days if this system had not been adhered to has not always been fully appreciated on site. /TRRL/

  • Availability:
  • Corporate Authors:

    Cement and Concrete Association

    52 Grosvenor Gardens
    London SW1W 0AQ,   England 
  • Authors:
    • Pateman, J D
  • Publication Date: 1977-2


  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 30-31
  • Serial:
    • Volume: 11
    • Issue Number: 2
    • ISSN: 0010-5317

Subject/Index Terms

Filing Info

  • Accession Number: 00153900
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Analtyic
  • Files: ITRD, TRIS
  • Created Date: Oct 13 1977 12:00AM