TO CRACK OR NOT TO CRACK? THE PROBLEM OF THERMAL CRACKING

This article is concerned with the factors which affect the thermal cracking of concrete and the difference between thermal cracking and drying shrinkage. It also outlines an economic method of eliminating the problem. After a general introduction the author discusses early thermal contraction and shrinkage and examines the relative strains involved which indicate that early cracking cannot be attributed to drying shrinkage. The factors which affect the early thermal history of concrete are discussed, e.g. cement type, cement content, thickness, initial temperature of materials, ambient temperatures, formwork type and the method of striking formwork and curing the concrete. This is followed by a discussion of the factors which affect subsequent cracking which include aggregate type, the distribution of crack control steel, stress raisers, nature of restraint, restraint of joints, sequence of casting, joint spacing and the spacing of crack inducing joints. The article concludes with brief recommendations aimed at reducing concrete costs in relation to the thermal contraction associated with large pours. /TRRL/

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00105317
• Corporate Authors:

  Cement and Concrete Association

  52 Grosvenor Gardens
  London SW1W 0AQ,   England 
• Authors:
  • Turton, C
• Publication Date: 1974-11

Language

• English

Media Info

• Features: Figures; Photos; References;
• Pagination: p. 32-36
• Serial:
  • CONCRETE
  • Volume: 8
  • Issue Number: 11
  • Publisher: THE CONCRETE SOCIETY
  • ISSN: 0010-5317

Subject/Index Terms

• TRT Terms: Aggregates; Cement; Concrete; Concrete curing; Contraction; Costs; Cracking; Deformation; Formwork; Heat; Joints; Mix design; Restraint systems; Shrinkage; Steel; Temperature; Thermal degradation; Thermal properties; Thickness
• Uncontrolled Terms: Concrete cracking; Restraint
• Old TRIS Terms: Concrete shrinkage; Joint; Thermal shrinkage
• ITRD Terms: 4577: Aggregate; 4758: Cement; 4755: Concrete; 224: Cost; 5211: Cracking; 4702: Curing (concrete); 5595: Deformation; 3639: Formwork; 6743: Heat; 2998: Joint (structural); 4714: Mix design; 3422: Restraint (fixing); 4743: Shrinkage; 4542: Steel; 6722: Temperature; 5933: Thickness
• Subject Areas: Finance; Geotechnology; Highways; Materials; Planning and Forecasting; Safety and Human Factors; I32: Concrete; I72: Traffic and Transport Planning;

Filing Info

• Accession Number: 00096789
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Jul 15 1975 12:00AM