The deformation characteristics of sand and other granular materials under hydrostatic compression are studied in the conventional triaxial apparatus using 4 × 4 in. (10 × 10 cm) specimens. Modifications have been made for measuring small axial strains and free end platens were used. The errors in testing have been estimated and their effect was evaluated. Different kinds of granular materials were tested to study the effect of the physical properties of the material on its deformational behavior.The results showed that the total deformation of a mass of sand subjected to a hydrostatic compression is generally not recoverable, and can be divided into elastic (recoverable) and sliding (irrecoverable) components. It has also been found out that for a dense specimen of sand most of the total deformation is recoverable, since the sliding component of deformation represents only a small fraction of the total deformation. The results also showed that for the very dense specimen axial and radial strains were nearly equal which implies that the material behaves isotropically. On the other hand for a loose specimen the sliding component of deformation becomes large and thus the total deformation of the specimen cannot be considered completely elastic. Furthermore axial and radial strains of the loose specimen were not equal.
Deformation Characteristics of Granular Materials in Cyclic One-Dimensional Loading Tests
