Summary: | The drained stress-strain, volume change, and strength behaviors of sand with cross-anisotropic fabric were studied in triaxial compression tests. Dense specimens with square cross-sections, height-to-diameter (H/D) ratios of 1.0 and 2.5, and lubricated ends were employed. Specimens consisting of relatively long, flat sand grains were prepared with cross-anisotropic grain structure, whose axis of rotation was inclined at various orientations from vertical to horizontal. The specimen boundary conditions (flexible membrane and lubricated, rigid end plates) had different effects on the results for specimens with H/D = 1.0 and 2.5. The specimens with H/D = 2.5 exhibited distinct, but temporary drops in their prefailure stress-strain curves, and the friction angles changed in a consistent pattern over a range of 5.5°. In comparison, the specimens with H/D = 1.0 showed more smooth stress-strain behavior, and their friction angles were essentially constant with very little effect of orientation
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