A high-pressure, thick-walled hollow cylinder test device has been perfected to explore the consequences of stress paths which are typical of pressuremeter configurations, tunnelling, or shafting in soil materials. Several features have been incorporated to facilitate data gathering, and the device is readily adaptable toK0or standard compression and extension triaxial tests. It has been used on tests in artificially prepared dense sand specimens constructed by a freezing technique, and will be used in an extensive study of the behavior of oil sands. Typical results of tests on dense Ottawa sand (C-109) are presented.