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A calibration chamber has been developed to conduct laboratory-controlled cone penetration tests in unsaturated soils. The chamber allows independent application of lateral and vertical pressures to an unsaturated soil specimen. Horizontal pressure is applied by cell water pressure pushing on a rubber membrane enclosing the specimen, while vertical pressure is maintained by a hydraulic loading ram at the base of the specimen. Suction is controlled using the axis- translation technique. Air pressure is applied to the top of the chamber where it spreads uniformly across the top of the specimen. Pore-water pressure is applied through eight high air-entry value porous disks embedded in the bottom plate. A particularly original aspect of the chamber design is the specimen formation system comprising four moveable cylinder quarters, which enables the creation of specimens of repeatable properties from a variety of soil types. The results of typical cone penetration tests conducted on dry, saturated, and unsaturated sand specimens are presented and highlight the contribution of suction to cone penetration resistance. Key words: unsaturated soil, suction, cone penetration test, calibration chamber, specimen formation, axis-translation technique. Une chambre de calibrage a ete deeveloppeee pour effectuer des essais de penetration au cone controles en laboratoire pour des sols non satures. La chambre permet d'appliquer des pressions laterales et verticales de facjon independantes sur un echantillon de sol non sature. La pression horizontale est appliquee par la pression de l'eau sur la cellule qui pousse sur une membrane en caoutchouc qui entoure l'echantillon, tandis que la pression verticale est maintenue par un belier de chargement hydraulique a la base de l'echantillon. La succion est controleea l'aide de la technique de translation de l'axe. La pression d'air est appliqueiea la partie superieure de la chambre et est distribuee uniformement sur le dessus de l'echantillon. La pression interstitielle est appliquee par huit disques poreux ayant une pression a l'entree d'air eleveie places dans la plaque du bas de la chambre. Un aspect original du design de la chambre est le systeme de formation des echantillons, qui comprend quatre quarts de cylindre mobiles, ce qui assure la creation d'echantillons avec des proprieetes reproductibles pour une variete de types de sols. Les resultats d'essais de penetration au cone typiques realises sur des echantillons de sable sec, sature; et non sature; sont presentes et mettent en evidence la contribution de la succion a la resistance a la peneetration du cone. Mots-cles: sol non sature, succion, essai de peenetration au cone, chambre de calibrage, formation d'eechantillons, technique de translation de l'axe. [Traduit par la Redaction], Introduction The engineering behaviour of unsaturated soils is complex and influenced by many factors including applied stresses, soil type, structure, density, and suction. Most notably, suction increases the soil's strength [...]

SUMMARY The problem of drained cavity expansion in soils of finite radial extent is investigated. Cylindrical and spherical cavities expanded from zero radius subjected to either constant stress or zero displacement at the finite boundary are considered. The generalised analytical solution procedure presented enables more advanced constitutive models to be implemented than have been possible in previous studies. Results generated for Sydney quartz sand highlight substantial differences between cavity limit pressures for the two boundary conditions and for boundaries of finite and infinite radial extent. This is of significance in accounting for boundary effects when interpreting cone penetration tests conducted in calibration chambers. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]