CRUSHED STONE SCREENINGS USED AS FINE AGGREGATE FOR CONCRETE

BECAUSE OF THE SCARCITY OF NATURAL SAND DEPOSITS IN NORWAY, CRUSHED ROCK MATERIALS ARE USED AS AGGREGATES FOR CONCRETE ON SOME CONSTRUCTION SITES. TESTS ON CRUSHED STONE SCREENINGS EMPLOYED AS FINE AGGREGATE HAVE BEEN CARRIED OUT AT THE NORWEGIAN INSTITUTE OF TECHNOLOGY THE RESULTS OF WHICH ARE: 1) FOR A GIVEN WATER-CEMENT RATIO, CRUSHED STONE SCREENINGS REQUIRE A GREATER QUANTITY OF CEMENT PASTE THAN NATURAL SAND IN ORDER TO OBTAIN THE SAME CONCRETE CONSISTENCY; 2) CRUSHED STONE SCREENINGS CONTAIN A HIGHER PROPORTION OF FINES; 3) FOR CRUSHED STONE SCREENGINGS THE FINE TO COARSE AGGREGATE RATIO SHOULD BE SLIGHTLY HIGHER THAN FOR NATURAL SAND; 4) WITH A HIGH WATER CEMENT RATIO CONCRETE CONTAINING CRUSHED STONE SCREENINGS IS COARSER AND MORE READILY SUBJECT TO BLEEDING THAN NATURAL SAND CONCRETE; 5) IF SUITABLE ROCK IS USED CRUSHED STONE CONCRETE STRENGTH CAN EXCEED THAT OF NATURAL SAND CONCRETE FOR A GIVEN WATER CEMENT RATIO. THIS APPLIES TO COMPRESSIVE AND TENSILE STRENGTH; AND, 6) IF WATER CEMENT RATIO IS HIGH AND THE PROPORTION OF AIR ENTRAINING AGENT SMALL, CRUSHED STONE CONCRETE HAS A LOWER RESISTANCE TO WEATHER THAN NATURAL SAND CONCRETE; IF THE WATER CEMENT RATIO IS LOW AND ENTRAINED AIR CONTENT IS BETWEEN 3 AND 6 PER CENT, NO DIFFERENCE IS OBSERVED.

• Authors:
  • Colbjoernsen, A
• Publication Date: 1972

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 119-32
• Serial:
  • Nordisk Betong /Sweden/
  • Volume: 16
  • Issue Number: 2

Subject/Index Terms

• TRT Terms: Aggregate mixtures; Air entraining agents; Bleeding; Cement paste; Coarse aggregates; Concrete; Concrete aggregates; Concrete construction; Consistency; Crushed rock; Durability; Fine aggregates; Sand; Screenings; Water cement ratio
• Old TRIS Terms: Concrete consistency
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00214325
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: TRIS
• Created Date: May 24 1974 12:00AM