Freezing and Cyclic Triaxial Behavior of Sands

Most analyses of the seismic response of natural sand deposits involve laboratory cyclic triaxial testing of undisturbed samples. However, obtaining undisturbed sand samples, transporting and then assembling them in a triaxial chamber with minimal disturbance is no easy task. A procedure currently in practice is to sample using thin wall Shelby tubes, allow the sample to drain while maintaining the tube vertical, and freeze the sample to minimize further disturbance during transportation, storage, and assembly for testing. However, this method assumes a priori that freezing does not affect the cyclic strength. Even though some cyclic triaxial investigations of liquefaction behavior have been conducted using frozen specimens, no data are available to show what effect, if any, freezing may have had. In this context, this investigation examines the effects of freezing on the cyclic triaxial behavior of sands.