WEBREVIEW

Estimation Of The Porosity Of Portland Cement Pastes Using Backscattered Electron Image

Ash J. E., Mellas M., Mezghiche B. — 2008-10-29T09:49:23Z

Microscopy plays an important role in the examination of cementitious materials. Electron-optical techniques allow
examination of microstructural details. The increased application of scanning electron microscopy in cement and concrete
investigations has brought attention to the estimation of the porosity. Backscattered Electron image has been established as a
method for quantitative analysis of hardened cement paste. This paper describes work and its application to Ordinary Portland
cement paste. Results show that the technique can be used to determine the porosity of Portland cement pastes. The success of
these investigations is, influenced by the type and quality of specimen preparation. In particular, backscattered electron and Xray
imaging modes are influenced by the specimen surface characteristics, with the ideal surface being highly polished. The technique can be a powerful tool to determine this essential factor of durability in concrete materials.

The Use Of Angular Velocity Vector In Shell Structures

Chebili R., Izemouren O., Mellas M., Mezghiche B. — 2008-10-25T13:10:08Z

In the following work, the principle of deformation is investigated using a new parameter called the angular velocity. The deformed element of surface is fully defined by this new parameter that is whenever the element of the reference surface undergoes a motion the three components of angular velocity define completely this motion.

- Numéro 06 / Angular velocity, Structure

ETUDE NUMERIQUE DU FACTEUR DE PORTANCE NΓ POUR UNE FONDATION FILANTE ET CIRCULAIRE

Benmeddour D., Mabrouki A., Mellas M. — 2008-03-05T14:04:20Z

Le problème d'évaluation de la capacité portante est largement étudié en tenant compte des différents paramètres géométriques et mécaniques. Les calculs sont basés sur la méthode d'équilibre limite, la méthode de ligne de glissement et la méthode d'analyse limite. Malgré la diversité dans les méthodes de calcul, l'écart entre les valeurs des facteurs de portance est très large
surtout pour les grandes valeurs de l'angle de frottement et l'angle d'interface.
Cet article vise d'une part l'estimation numérique du (...)

- Numéro 08 / Fondation filante et circulaire, Capacité portante, Modélisation numérique, Charge centrée