THE SUITABILITY OF SLAG FOR STRUCTURAL BACKFILLING

The results are discussed of free-swell tests carried out on samples of blast furnace slag having application in backfilling operations. Research has shown that the swelling or expansivity of slags resulting from iron- and steel-making operations is caused by the hydration of free calcium and magnesium oxides. The rate at which this takes place is dependant upon the protection given to the slag after its production. Slags can be divided into two types - (1) blast furnace slags which possess generally uniform properties, and (2) slags from steel-making operations which can vary considerably in properties. Samples of milled blast furnace slag were used to perform free-swell tests for a total period of 300 days when the uncompleted expansion was about 0.17 per cent of linear length. It is concluded that before slags are considered for backfilling operations beneath settlement- or heave-sensitive structures, long-term expansivity tests should be carried out to estimate likely ranges of movement. /TRRL/

• Corporate Authors:

  Pithead Press Proprietary Limited

  4th Floor, Wynrop House, 91 Mooi Street
  Johannesburg,   South Africa 
• Authors:
  • Harris, G M
• Publication Date: 1976-9

Language

• English

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: 9 p.
• Serial:
  • Construction in Southern Africa
  • Volume: 21
  • Issue Number: 6
  • Publisher: Pithead Press Proprietary Limited

Subject/Index Terms

• TRT Terms: Backfilling; Breakwaters; Calcium; Earthwork; Expansion; Hydration; Magnesium; Oxides; Slag; Swelling; Tests; Trench backfill
• ITRD Terms: 7178: Calcium; 3653: Earthworks; 2801: Embankment; 6720: Expansion; 7195: Hydration; 7188: Magnesium; 7372: Oxide; 4561: Slag; 5203: Swelling (soil); 6255: Test
• Subject Areas: Geotechnology; Highways; Marine Transportation; Materials; I33: Other Materials used in Pavement Layers;

Filing Info

• Accession Number: 00149092
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: Analytic
• Files: ITRD, TRIS
• Created Date: Jul 2 1977 12:00AM