AN APPRAISAL OF THE ULTRASONIC PULSE TECHNIQUE FOR DETECTING VOIDS IN CONCRETE

The paper describes an experimental systematic approach to precisely determine the extent of deep-seated voids or honeycombed patches in hardened concrete. Different sizes of void were cast into blocks of different mixes and strengths; a layer of mild steel bars were placed away from the voids near to the bottom of the concrete blocks at various spacings. Details are given of the experimental method, using a pundit machine, and results are tabulated and discussed. A statistical method is proposed for tracing the boundaries of the void provided the variability of measured pulse velocities in the concrete surrounding the void is low. The periphery of the void can be checked by adjusting pulse velocities inside the void boundaries. It was found that steel bars perpendicular to the pulse transmission had a negligible effect. The reverse was true of those bars in the same direction and measurements taken in their zone of influence should be excluded from analysis. /TRRL/

  • Availability:
  • Corporate Authors:

    Cement and Concrete Association

    Wexham Spring
    Slough SL3 6PL, Buckinghamshire,   England 
  • Authors:
    • CHUNG, H W
  • Publication Date: 1978-11

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 25-8
  • Serial:
    • CONCRETE
    • Volume: 12
    • Issue Number: 11
    • Publisher: THE CONCRETE SOCIETY
    • ISSN: 0010-5317

Subject/Index Terms

Filing Info

  • Accession Number: 00195419
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Aug 15 1979 12:00AM