NEW APPROACH TO STRAIN RATE SENSITIVITY OF CONCRETE IN COMPRESSION

A constitutive law to model the strain-rate-dependent compression behavior of concrete is proposed. It is derived from a mechanical model, where inertia effects influence damage formation. To verify this model, an experimental method based on the split Hopkinson bar (SHB) technique is described--one that considers the special properties of concrete specimens. Compressive stress waves with varying peak values and durations were realized using an extended SHB device. Dynamic stress-strain relations, which differ considerably from the corresponding static relations, are derived for the investigated load histories and are modeled with the proposed dynamic constitutive law. While a number of compression load histories are sustained by the specimens, others result in failure. Thus, a dynamic failure criterion is established, connecting failure occurrence, peak stress, and the time to reach the peak stress.

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  • English

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Filing Info

  • Accession Number: 00779737
  • Record Type: Publication
  • Contract Numbers: 7 T07A 012 08, PolyU 70/96E
  • Files: TRIS
  • Created Date: Dec 28 1999 12:00AM