Endochronic theory for inelasticity and failure analysis of concrete structures

Technical Report · Wed Dec 01 04:00:00 EST 1976

DOI:https://doi.org/10.2172/7324674· OSTI ID:7324674

Bazant, Z. P.; Bhat, P. D.; Shieh, C. L.

A gradual accumulation of inelastic strain can be most conveniently described in terms of the so-called intrinsic time, whose increment depends on the time increment as well as the strain increments. This approach, which gives a particularly simple description of irreversibility of strain at unloading and cyclic loading, was previously developed for metals and is extended herein to concrete by introducing the hydrostatic pressure sensitivity of inelastic strain, the inelastic dilatancy produced by deviator strains, and the strain-softening tendency at high stress. Failure envelopes are obtained as a collection of the peaks of stress-strain diagrams. By comparison with experimental data from the literature, it is demonstrated that the proposed model predicts quite closely: stress-strain diagrams for concretes of different strength; uniaxial, biaxial and triaxial stress-strain diagrams and failure envelopes; failure envelopes for combined torsion and compression, lateral strains and volume expansion in uniaxial and biaxial tests; the behavior of spirally confined concrete; hysteresis loops or repeated high compression; cyclic creep up to 10/sup 6/ cycles; the strain rate effect; the decrease of long time strength; and the increase of short-time strength due to low stress creep.

• Research Organization: Northwestern Univ., Evanston, IL (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 7324674
• Report Number(s): ORNL/Sub/4403-1
• Country of Publication: United States
• Language: English

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