INFLUENCE OF CONCRETE PROPERTIES ON IMPULSE HAMMER SPECTRUM AND COMPRESSION WAVE VELOCITY

A pilot study was performed to evaluate the influence of different properties of concrete on the contact time of the hammer head and pulse velocity of compression waves produced by two impact hammers of different mass (280 g and 1.25 g). Each impact hammer was instrumented so that the force introduced to the test specimen could be measured. Differences in measured contact time for each hammer showed how significant the influence of the factor under test was in analysing output from impact-echo tests on concrete. The pulse velocity was calculated using an ultrasonic digital tester which gave the velocity of compression waves. Two sets of 100 mm cubes were made with different mix ratio for this pilot study. The contact time and pulse velocity were calculated and the compressive strength measured at different ages. The results showed that the contact time decreased and the pulse velocity increased with age. However, the mix proportions also affected the results. It was established that as the nominal contact time of the impact decreased so the actual contact time achieved was more affected by the mix proportions and general condition of the concrete.

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  • Corporate Authors:

    Elsevier

    The Boulevard, Langford Lane
    Kidlington, Oxford  United Kingdom  OX5 1GB
  • Authors:
    • Martin, J
    • FORDE, M C
  • Publication Date: 1995

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00720845
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: May 24 1996 12:00AM