Numerical study of elastic properties of ITZ in hydrating cement paste

Title: Numerical study of elastic properties of ITZ in hydrating cement paste
Author(s): V. Šmilauer, Z. Bittnar
Paper category : conference
Book title: 2nd International RILEM Symposium on Advances in Concrete through Science and Engineering
Editor(s): J. Marchand, B. Bissonnette, R. Gagné, M. Jolin and F. Paradis
Print-ISBN: 2-35158-003-6
e-ISBN: 2351580028
Publisher: RILEM Publications SARL
Publication year: 2006
Nb references: 10
Language: English

Abstract: The interfacial transition zone (ITZ) represents a serious problem when homogenizing mechanical properties of cement mortar or concrete. Although many mechanisms contribute to its origin and evolution, we believe that the wall effect is of the highest importance. Commonly accepted thickness of ITZ, as it appears around the aggregates, is in the range from 0 to 50 ?m. Cement hydration program CEMHYD3D extended with the percolation filtering will be used for the reconstruction of the ITZ and following hydration. Imposing periodic boundary conditions and using FEM leads to effective homogenized elastic properties of ITZ. Depending on the cement fineness, the reduction of Young’s modulus against bulk paste was found up to 40 % while Poisson’s ratio remained almost the same for the ITZ thickness of 24 ?m. Validation on mortar samples shows that the results are in accordance with experiment.

Keywords: Interfacial transition zone, elastic properties, homogenization, cement paste

Online publication: 2006-08-02
Classification: 3.2 Theme 2: From Fresh to Hardened Concrete
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/2351580028.079