Accession Number : ADA301935

Title :   Numerical Simulation of Damage in Concrete.

Descriptive Note : Technical rept. 20 May 91-20 Jun 94,

Corporate Author : APTEK INC COLORADO SPRINGS CO

Personal Author(s) : Murray, Yvonne D. ; Lewis, Brett A.

PDF Url : ADA301935

Report Date : 01 NOV 1995

Pagination or Media Count : 139

Abstract : An elasto-plastic damage model for concrete and other geologic materials was implemented into the three-dimensional, nonlinear finite element code DYNA3D. The smooth-cap model contains an isotropic damage formulation for modeling strain-softening and modulus reduction, a three-invariant plasticity surface formulation to simultaneously fit triaxial compression and extension data, and a viscoplastic formulation for modeling strength enhancement at high strain rates. Separate formulations for brittle and ductile damage are implemented. The model captures the essential features of concrete behavior: shear enhanced compaction. dilatency. pre-peak hardening, post-peak softening, modulus reduction, and localized damage accumulation. Selected benchmark applications demonstrate the fit of the model to standard laboratory test data, bending analysis of reinforced concrete slabs, and comparisons of single element and multi-element laboratory test simulations. The multi-element simulations predict diagonal damage patterns and splitting, which are typical failure modes of unconfined compression test specimens. The multi-element simulations also predict more severe softening than the single-element simulations.

Descriptors :   *MATHEMATICAL MODELS, *DAMAGE ASSESSMENT, *REINFORCED CONCRETE, *ELASTOPLASTICITY, TEST AND EVALUATION, VISCOPLASTICITY, COMPRESSION, SIMULATION, EXPERIMENTAL DATA, LABORATORY TESTS, OPTIMIZATION, HIGH RATE, DAMAGE, FINITE ELEMENT ANALYSIS, FORMULATIONS, NUMERICAL ANALYSIS, ELASTIC PROPERTIES, FAILURE, CONCRETE, BENDING, GEOLOGY, STRAIN RATE, THREE DIMENSIONAL, BRITTLENESS, ISOTROPISM, STRENGTH(GENERAL), STANDARDS, PLASTIC PROPERTIES, DUCTILITY, NONLINEAR ANALYSIS, ACCUMULATION, COMPACTING, MICROCRACKING, TRIAXIAL STRESSES.

Subject Categories : Laminates and Composite Materials
      Operations Research
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE