Hollow cylinder torsional shear tests to evaluate the role of principal stress directions on cyclic resistance

摘要

A new hollow cylinder torsional shear device commissioned at Carleton University was used to study the effects of principal stress rotation on cyclic resistance. Specimens at identical initial states were subject to a given cyclic stress ratio, but along stress paths that impose different levels of stress rotation. The paths explored included smooth, continuous rotation of principal stress directions, and sudden jump rotation. These results suggest that the general notion that the weakest response is expected when the major principal stress is aligned with the bedding planes may not be valid under cyclic loading, and cyclic simple shear tests provide a convenient means of determining the cyclic resistance.