THE EFFECTS OF LIGNOSULPHONATE-BASED ADMIXTURES ON DRYING SHRINKAGE OF CEMENT PASTE AND CONCRETE

Data are presented on the influence of lignosulphonate-based admixtures used either with or without the accelerating admixtures calcium chloride or triethanolamine, on the drying shrinkage of concrete, after various periods of drying in air at 50 percent relative humidity and 72 degrees F. Shrinkage effects were studied for: (a) - concretes and cement pastes in which the admixtures were simply added without changing mix proportions, (b) - concretes in which the admixture use was accompanied by a reduction in water and cement content to maintain strength and workability, (C) - concretes in which the admixture use was accompanied by a reduction in water content to maintain workability - with a consequent increase in strength. The intrinsic effect of lignosulphonate admixtures was to increase early drying shrinkage, as observed from studies in which the admixture was simply added without changing mix proportions. The effect was, however, not significant after prolonged drying. The inclusion of accelerating admixtures produced additional increases in drying shrinkage, the resultant shrinkage being greater at both early and long-term periods. When admixture use was accompanied by a reduction in water and cement, or water content, the consequent paste reduction counteracted the intrinsic tendency of the lignosulphonate-based admixtures to increase shrinkage. The net shrinkage was either slightly increased or decreased, depending on the actual admixture used and the length of the drying period. (a). The number of the covering abstract of the conference is IRRD abstract no. 213776. /TRRL/

  • Supplemental Notes:
    • Presented at the First Australian Conference on Engineering Materials.
  • Corporate Authors:

    University of New South Wales

    School of Civil Engineering, Anzac Parade
    Kensington, New South Wales  Australia  2033
  • Authors:
    • Morgan, D R
  • Publication Date: 0

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 19 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00129545
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Conf Paper
  • Files: ITRD, TRIS
  • Created Date: May 14 1976 12:00AM