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Effective elastic properties of degraded and non degraded cement pastes using various micromechanics schemes and numerical simulations



Title: Effective elastic properties of degraded and non degraded cement pastes using various micromechanics schemes and numerical simulations
Author(s): M. Ben Haha, B. Bary, E. Adam, P. Montarnal
Paper category : conference
Book title: International RILEM Symposium on Concrete Modelling - ConMod '08
Editor(s): E. Schlangen and G. De Schutter
Print-ISBN: 978-2-35158-060-8
e-ISBN: 978-2-35158-076-9
Publisher: RILEM Publications SARL
Publication year: 2008
Pages: 619 - 627
Total Pages: 9
Nb references: 15
Language: English


Abstract: A classical problem in mechanics of solids is the determination of the effective elastic properties of a composite materials made up of a statistically isotropic random distribution of isotropic and elastic inclusions embedded in a continuous, isotropic and elastic matrix. The cement pastes are characterised by a high particle concentration and phase contrasts, in particular for degraded materials consecutive to leaching that exhibit important porosity levels. The macroscopic properties of these multiphase compounds depend on the properties of the constitutive phases, and the microstructures of the compounds. The ability of the classical and simple homogenisation schemes compared to more sophisticated and complex methods for the estimation of the elastic properties is then questionable. This paper compares the performance of several homogenisation methods, based on various approaches and/or concepts, for the determination of the overall elastic properties of cement pastes from the local properties of the components. The comparison of the schemes is based on their ability to reproduce the mechanical characteristics of the cement paste material either experimental or given by numerical simulations: bulk, shear and Young modulus. Three dimensional numerical simulations are thus performed to compute for each generated cement paste accurate values of these mechanical properties. For these simulations, the cement paste is considered as a matrix of CSH in which are embedded inclusions of anhydrous products and other hydration products. The aptitude of the different models to produce mechanical properties resulting from the same generated composites as the one obtained with the numerical simulation is finally analysed.


Online publication: 2009-06-15
Publication type : full_text
Public price (Euros): 0.00