Accession Number : ADP001721

Title :   Constitutive Relations of Concrete Subjected to a Varying Strain Rate,

Corporate Author : NORTHWESTERN UNIV EVANSTON IL

Personal Author(s) : Shah,S. P.

Report Date : MAY 1983

Pagination or Media Count : 4

Abstract : Experiments conducted on concrete subjected to impact loading in uniaxial tension, uniaxial compression and in flexure, indicate that (1) the strain effects in concrete are not isotropic, (2) the stress-strain curves becomes less non-linear with increasing strain rate and (3) the rate of growth of internal microcracking decreases with increasing strain rate. A continuous damage model is proposed to establish the constitutive relationship of concrete. To include the effect of strain rate on internal damage, an inertial term is introduced in the damage evolution equation. The damage is expressed as a tensor quantity. The Hermholtz free energy function is expressed in terms of both the invariants of strain tensors and damage tensors. Equations predicted by the model are compared with the experimental results. (Author)

Descriptors :   *Concrete, *Strain rate, Symposia, Impact, Loads(Forces), Tensile properties, Compressive properties, Flexural properties, Stress strain relations, Microcracking, Mathematical models, Damage assessment, Tensors, Equations, Mathematical analysis

Distribution Statement : APPROVED FOR PUBLIC RELEASE