Materials and Structures

, 23:3 | Cite as

From pore size distribution to an equivalent pore size of cement mortar

  • H. W. Reinhardt
  • K. Gaber
Article

Abstract

An experimental and theoretical study has been performed with the aim of quantifying pore size distribution curves and correlating them with water and oxygen permeability. Twenty mortars have been investigated which contained Portland cement, blast-furnace slag cement and silica fume as a binder. Admixtures have been used as well. The water-cement ratio varied between 0.4 and 0.75 and two curing conditions were applied. By the use of mercury intrusion porosimetry, the pore size distribution was determined. Water and oxygen permeability have been measured in the steady state. Equivalent pore sizes have been calculated which quantify the pore size distribution by a single number. This number is not a constant but depends on the physical transport mechanism. It is shown that equivalent pore size and porosity together are sufficient to predict the physical properties with an acceptable accuracy.

Keywords

Pore Size Distribution Portland Cement Silica Fume Water Permeability Pore Radius 

Resumé

On a mené une étude expérimentale et théorique afin de quantifier les courbes de distribution dimensionnelle des pores et de les mettre en corrélation avec la perméabilité à l'eau et à l'oxygène. On a examiné 20 mortiers contenant du ciment Portland, du ciment de laitiers et des fumées de silice comme liant. On a également utilisé des adjuvants.

Le rapport eau-ciment obtenu variait de 0,4 à 0,75; les conditions de cure étaient de deux sortes. On a déterminé la distribution dimensionnelle des pores par la porosimétrie au mercure. On a mesuré la perméabilité à l'eau et à l'oxygène en régime permanent. On a calculé un équivalent porosimétrique qui traduit par une seule quantité la distribution dimensionnelle des pores. Le nombre obtenu n'est pas une constante mais dépend du mécanisme de transfert. On montre que l'équivalent porosimétique et la porosité suffisent seuls à prédire les propriétés physiques avec une exactitude acceptable.

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Copyright information

© RILEM 1990

Authors and Affiliations

  • H. W. Reinhardt
    • 1
  • K. Gaber
    • 1
  1. 1.Darmstadt University of TechnologyDarmstadtFRG

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