Study on the Effects of Amount of Clay Contents on Undrained Behavior of Clayey Sands Under Anisotropic Consolidation Compression Stress by Means of Undrained Monotonic Triaxial Tests

The results of an experimental study on Firoozkuh sand with various clay contents (Kaolinit with PI=12) are presented. A series of anisotropic undrained triaxial tests were performed in consolidation stress 200KPa and different consolidation stress ratios in order to investigate the Induced anisotropic behaviour of clayey sands. The sand specimens had clay contents ranging from 0% to 30%. Anisotropic behaviour was observed by means of anisotropic compression triaxial tests in various consolidation stress ratio (KC) ranging from 0.5 to 0.88 in consolidation stress 200Kpa. It was observed that the induced anisotropic behavior of specimens changes suddenly at KC=0.63. pure sands have more stable behavior than sands with 15% clay, and specimens with 15% clay are more stable than specimens with 30% clay (except in Kc=0.5).

Keywords:

firoozkooh sand , monotonic triaxial test , induced anisotropy , clay , undrainedbehaviour , consolidation stress ratio (KC)