ADMIXTURES TO CONCRETE /IN SWEDISH/

THE USE OF ADMIXTURES CONSTITUTES AN IMPORTANT BRANCH OF CONCRETE ENGINEERING. THE KNOWLEDGE OF ADMIXTURE PROPERTIES AND THEIR BEHAVIOR IN CONCRETE IS IN NEED OF BEING DEEPENED, AND INVESTIGATIONS ARE REQUIRED FOR THIS PURPOSE. THE EFFECTS PRODUCED BY ADMIXTURES ON THE PROPERTIES OF THE CONCRETE ARE GROUPED AS FOLLOWS ACCORDING TO THE PERIODS OF TIME EFFECTS: (1) EFFECTS WHICH ARE CONFINED TO THE PERIOD OF CONCRETING (UP TO 1/2 OR 1 DAY), (2) SHORT TIME (TRANSITORY) EFFECTS (UP TO 2 TO 4 WEEKS), (3) DESIRED LONG TIME (PERMANENT) EFFECTS, AND (4) SLOWLY DEVELOPING HARMFUL EFFECTS. THE EFFECTS STUDY MEETS WITH CERTAIN DIFFICULTIES, WHICH ARE OBVIOUSLY GREATEST IN GROUPS 3 AND 4. THE RELATIVELY GREAT DIFFERENCES THAT CAN EXIST BETWEEN THE TEST SPECIMENS WHICH ARE USED IN THE LABORATORY AND THE CONCRETE IN THE STRUCTURE ITSELF ARE EMPHASIZED. FOR INSTANCE, THE DIFFERENCES MAY CONCERN THE VOID CONDITIONS IN THE CONCRETE WHICH MUST COMPLY WITH REQUIREMENTS FOR FROST RESISTANCE. CONCRETE CORES DRILLED FROM STRUCTURES SHOULD THEREFORE BE USED AS TEST SPECIMENS TO A GREATER EXTENT THAN THEY ARE AT PRESENT TIME. THE FOLLOWING PROBLEMS ARE AT PRESENT DEEMED TO DESERVE FUTURE RESEARCH: (1) TEST ON ADMIXTURES AND METHODS OF TESTING, (2) INVESTIGATIONS WHICH DEAL WITH THE RISK OF SLOWLY DEVELOPING HARMFUL EFFECTS PRODUCED BY ADMIXTURES ON CONCRETE, (3) STATEMENT OF DATA WHICH SPECIFY THE PROPERTIES OF ADMIXTURES, (4) PROCEDURES EMPLOYED IN PRELIMINARY TESTS WHICH ARE CARRIED OUT ON CONCRETE ON THE SITE WHEN USE IS MADE OF ADMIXTURES, (5) STUDIES OF THE CORRESPONDENCE BETWEEN THE RESULTS OBTAINED FROM TESTS ON LABORATORY TEST SPECIMENS AND FROM TESTS ON CONCRETE CORES WHICH ARE DRILLED FROM THE STRUCTURE ITSELF, AND (6) INVESTIGATIONS WHICH SHOW HOW THE DESIRED PERMANENT EFFECTS ARE ATTAINED AND HOW DURABLE THEY ARE. OBSERVATIONS AND STUDIES OF HARMFUL EFFECTS WHICH MAY POSSIBLY MANIFEST THEMSELVES IN FINISHED CONCRETE STRUCTURES ARE NOTED. /RRL/A/

• Supplemental Notes:
  • Vol 11, No 3, PP 431-436
• Authors:
  • VUORINEN, J
• Publication Date: 1967

Media Info

• Serial:
  • Nordisk Betong /Sweden/

Subject/Index Terms

• TRT Terms: Admixtures; Behavior; Concrete; Concrete structures; Core samples; Crash investigation; Durability; Engineering; Impacts; Physical properties; Properties of materials; Specimens; Studies; Test procedures; Testing; Time
• Uncontrolled Terms: Concrete properties
• Old TRIS Terms: Cores; Test results; Time effects
• Subject Areas: Highways; Materials; Safety and Human Factors;

Filing Info

• Accession Number: 00212966
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: Aug 26 1970 12:00AM