Association of macroscopic laboratory testing and micromechanics modelling for the evaluation of the poroelastic parameters of a hardened cement paste

TL;DR

This study combines macro-scale laboratory tests with micromechanics modeling to evaluate the poroelastic parameters of hardened cement paste, revealing insights into active porosity and enabling parameter extrapolation across different compositions.

Contribution

It introduces a multi-scale homogenization approach calibrated with experimental data to determine poroelastic parameters of cement paste, including active porosity.

Findings

Active porosity is smaller than total porosity in cement paste.

The homogenization model successfully extrapolates parameters for different water-to-cement ratios.

Poroelastic parameters for ideal drained conditions are quantitatively evaluated.

Abstract

The results of a macro-scale experimental study performed on a hardened class G cement paste [Ghabezloo et al. (2008) Cem. Con. Res. (38) 1424-1437] are used in association with the micromechanics modelling and homogenization technique for evaluation of the complete set of poroelastic parameters of the material. The experimental study consisted in drained, undrained and unjacketed isotropic compression tests. Analysis of the experimental results revealed that the active porosity of the studied cement paste is smaller than its total porosity. A multi-scale homogenization model, calibrated on the experimental results, is used to extrapolate the poroelastic parameters to cement pastes prepared with different water-to-cement ratio. The notion of cement paste active porosity is discussed and the poroelastic parameters of hardened cement paste for an ideal, perfectly drained condition are evaluated using the homogenization model.