Thermo-mechanical behaviour of a compacted swelling clay

Compacted unsaturated swelling clay is often considered as a possible buffer material for deep nuclear waste disposal. An isotropic cell permitting simultaneous control of suction, temperature and pressure was used to study the thermo-mechanical behaviour of this clay. Tests were performed at total suctions ranging from 9 to 110 MPa, temperature from 25 to 80 degrees C, isotropic pressure from 0.1 to 60 MPa. It was observed that heating at constant suction and pressure induces either swelling or contraction. The results from compression tests at constant suction and temperature evidenced that at lower suction, the yield pressure was lower, the elastic compressibility parameter and the plastic compressibility parameter were higher. On the other hand, at a similar suction, the yield pressure was slightly influenced by the temperature; and the compressibility parameters were insensitive to temperature changes. The thermal hardening phenomenon was equally evidenced by following a thermo-mechanical path of loading-heating-cooling-reloading

An improved method of computing geometrical potential force (GPF) employed in the segmentation of 3D and 4D medical images

The geometric potential force (GPF) used in segmentation of medical images is in general a robustmethod. However, calculation of the GPF is often time consuming and slow. In the present work, wepropose several methods for improving the GPF calculation and evaluate their efficiency against theoriginal method. Among different methods investigated, the procedure that combines Riesz transformand integration by part provides the fastest solution. Both static and dynamic images have been employedto demonstrate the efficacy of the proposed methods

Wettability of reservoir core samples,

Wettability of reservoir core samples, S.P.E. paper 1968

Comportement du limon de Jossigny remanié soumis à une pression interstitielle négative

L'étude expérimentale du comportement du limon de Jossigny (wL = 37 ; IP = 19) sur différents chemins à pression interstitielle imposée (drainage-humidification, chemins triaxiaux normalement consolidés ou surconsolidés) montre que la logique des sols saturés et la notion classique de contrainte effective de Terzaghi restent valables tant que l'eau est la phase continue, c'est- à-dire, en première approximation, pour des teneurs en eau supérieures à la limite de retrait

Compressibilité des sols argileux de 10 1 à 10 8 Pa

International audienceCompressibilité des sols argileux de 10 1 à 10 8 P