Volume 27, Issue 1 (January 2004)
Liquefaction Testing of Layered Sand-Gravel Composites
The liquefaction characteristics of stratified sand-gravel composites are currently poorly understood, yet these materials are often encountered in alluvial and hydraulic fill deposits. To investigate the effect of soil layering on the cyclic resistance of sand-gravel composites, a research program was undertaken in which a series of undrained cyclic triaxial tests was performed on both uniform and layered sand-gravel composite specimens with gravel contents of 10, 30, 50, and 70%. Two methods of sample preparation were used for each soil type. These methods included pluviation through air (representing homogeneous soil conditions) and wet pluviation (representing layered soil conditions). The confining pressures ranged from 50 to 250 KPa. The results indicated that the method of sample preparation and the different soil fabric did not significantly influence the liquefaction resistance of the sand-gravel composites. It is also shown that the effects of confining pressure are similar for both homogeneous and layered soil conditions.