Modélisation Multi-échelle Du Comportement Mécanique Des Matériaux Cimentaires Soumis À la Carbonatation Ou À la Lixiviation
Author | : Hamid Ghorbanbeigi |
Publisher | : |
Total Pages | : 0 |
Release | : 2014 |
ISBN-10 | : OCLC:922008318 |
ISBN-13 | : |
Rating | : 4/5 (18 Downloads) |
Book excerpt: The objective of this thesis is to model the mechanical behavior of cement based materials, such as cement paste and concrete, which are subject to carbonation and leaching. These chemical reactions between the cementitious material and the surrounding aggressive environment lead to changes in the material microstructure and consequently on the mechanical behavior, and can have a significant impact on the durability of structures. To characterize the mechanical behavior of these chemically influenced materials, two different approaches are proposed in this thesis: the macroscopic and microscopic approach. In the first part, a macroscopic approach is used. The interest is to use a classical elastoplastic model to see the effect of carbonation and lixiviation on the elastic and plastic parameters. This model is then coupled with an interface model to describe the mechanical behavior and the failure process of cementitious materials, taking into account the localization of deformations on a shear band. In the second part, by taking advantage of micro-macro models, it is possible to explicitly link the microstructure evolution during the degradation to the mechanical behavior of the material. Two or three homogenization steps based on the modified secant method are needed to reach the macroscopic criterion. The predictive capabilities of micro-macro models proposed here have been demonstrated through a wide experimental validation.