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In steel ladles (steel industry) or in coal-fired power plants (energy production), the refractory linings anchored to the steel structure (casing) are subjected to significant thermal loadings which lead to cracking (owing to the difference between the thermal expansion coefficients). A first approach allows us to analyse the problem at a local scale: a smeared crack model permits the computation of the damage which is observed in an experimental test. But since a structure contains thousand of anchors, it is not possible to compute it with this model. An approach was therefore developed with a two-layered shell equivalent to the anchored lining and the casing. This model is identified with an inverse method and uses results from the first approach, validated by a bending test performed on a refractory lining specimen. The damage computing of a structure shows that it is very important to take the expansion joints into account.

The simulation of the drawing process for woven reinforcements aims at evaluating the possibility of forming a shape for a given fabric. The mode of deformation during the forming of woven reinforcements is very specific and different from that for metal sheets. Knowledge of fabric behaviour is necessary. In the present work, this is studied experimentally by means of biaxial tests that bring out the influence of the geometric non-linearity, at the mesh scale, on the macroscopic behaviour of the fabric. Models based on bar and yarn theories, are identified from these tests and used in a specific finite-element formulation for fabrics. These elements are efficient since they take into account only the tension stiffness of the yarns (the only one present in a fabric). Three-dimensional simulations of the elementary mesh supplement this study with local information.

Different matrix microcracking mechanisms are observed in ceramic-matrix composites under complex loading conditions. These mechanisms are introduced in the proposed model by using an anisotropic damage theory, which takes into account the effects due to microcrack opening and closure, according to the state of the stress tensor (the behaviour is different in tension and in compression). One difficulty is the identification of this model for the woven SiC SiC composite under study. Classical uniaxial tests (at 0 ° and 45 °) are not sufficient to identify the model completely. A combined biaxial tension test is defined in order to determine the missing parameters. Internal pressure tests on tubes qualitatively validated the model.