LOK-TEST AND CAPO-TEST DEVELOPMENT AND THEIR APPLICATIONS

Two pull-out systems for testing the in situ compressive strength of concrete are presented, lok test and capo test. With the lok test, 25mm of the concrete (usually the surface layer) is tested by pulling a pre-embedded disc towards a counterpressure ring placed on the testing surface. With the capo test the concrete is tested at random on the same principle, but by drilling and expanding a special insert in the concrete which is then pulled out. In this configuration, failure of the concrete is due to compression, and hence the pulling force is a direct measure of the compressive strength. Calibration data from 19 major projects in Denmark, Sweden, Norway, the Netherlands, the USA and Canada are presented, totalling 4774 pull-outs and 4202 compression tests (cylinder and cube). Based on experience so far, general relationships for cylinder strength and cube strength are recommended for normal concrete with maximum aggregate size not greater than 38mm. Variation in the pull-out tests is shown to be of the same order as for the standard cylinder or the standard cube. (TRRL)

• Corporate Authors:

  Thomas Telford Limited

  London,   United Kingdom 
• Authors:
  • PETERSEN, C G
• Conference:
  • Institution of Civil Engineers, Proceedings, Pt 1
• Publication Date: 1984-5

Media Info

• Features: Figures; References;
• Pagination: p. 539-549
• Serial:
  • Volume: 76

Subject/Index Terms

• TRT Terms: Accuracy; Calibration; Compression; Compression tests; Concrete; Concrete tests; Correlation analysis; Cubes; Field tests; Measurement; Pull out test; Strength of materials; Test procedures; Tests
• Old TRIS Terms: Compressive strength tests
• ITRD Terms: 5532: Compression; 4755: Concrete; 6527: Correlation (math, stat); 6457: Cube; 6226: In situ; 6136: Measurement; 6259: Pull out test; 5544: Strength (mater); 6255: Test
• Subject Areas: Data and Information Technology; Highways; Materials; Planning and Forecasting; I32: Concrete; I72: Traffic and Transport Planning;

Filing Info

• Accession Number: 00388910
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Oct 30 1984 12:00AM