A NEW MODEL FOR ANISOTROPIC DAMAGE IN CONCRETE ANDITS APPLICATION TO THE PREDICTION OF FAILURE OF SOMECONTAINMENT VESSEL

摘要

The aim of this paper is to propose a new model for damage in concrete structures which incorporates suchcomplex features as damage anisotropy and asymmetry between tension and compression, while being expressedin a format well suited for numerical applications and involving a limited number of material parameters which canbe determined from standard experiments. A crude version of the model involving a single tensorial internalvariable representing damage in tension, and a single material parameter, is presented first. The predictions of thissimple model are satisfactory in simple tension, but not so in simple compression. As a remedy, variousrefinements are then introduced in a second version of the model involving an additional tensorial or scalar internalvariable representing damage in compression, and five additional material parameters. An example ofdetermination of the model parameters using experimental stress-strain curves in simple tension and compression,plus failure envelopes in biaxial tension/compression, is presented next. The model is finally applied to thenumerical prediction of the failure of some containment vessel subjected to some large internal pressure, with acomparison with calculations based on a simpler isotropic variant of the model using a single scalar damagevariable. The results illustrate the relevance of models incorporating both asymmetry between tension andcompression and anisotropy of damage for simulations of industrial concrete structures.