A Geometric Approach to Thermomechanics of Dissipating Continua (original) (raw)
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Introduction to the thermomechanics of configurational forces
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HAL (Le Centre pour la Communication Scientifique Directe), 2021
Microcracks are known to affect the behaviour of the materials and several modelling studies are devoted to finding their effective elasticity. This paper aims to extend such investigation to thermal properties, concerning both the steady-state conduction and the thermoelasticity. Accounting simultaneously for the anisotropy induced by microcracks orientation and for their unilateral effect (different behaviour whether they are open or closed) remains a difficult task. In this work, 3D homogenization-based approaches are developed to derive closed-form estimations of the effective thermal properties of a microcracked media with arbitrarily oriented microcracks, either open or closed.
Unilateral behaviour of microcracks and thermal conduction properties: a homogenization approach
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Damaging effects of microcracks on the elastic properties of brittle materials (rocks, concrete, ceramics) have been extensively studied through experiments and modelling approaches. In the latter case, the homogenization (up-scaling) technique appears as an effective tool to provide the overall properties from the microstructural features of the material. Especially for microcracks, main difficulties arise from: (i) the anisotropy induced by the oriented nature of defects, (ii) their ability to be open or closed according to tension or compression loading and to influence differently the overall response of the material. Such unilateral behaviour is typical of contact problems related to that kind of defects. Regarding the thermal properties of microcracked media, very few investigations on the effects have been done in the literature, even on the experimental point of view. Some micro-macro modelling works have been proposed to derive effective properties of a given Representative...