M. Dargahi - Postgraduate Student of Geotechnical Eng., Faculty of Civil Engineering, University of Tehran
A. Ghalandarzedeh - Assistant Professor, Faculty of Civil Engineering, University of Tehran, Iran.

The effects of the amount of clay on the undrained behaviour of clayey sands under undrained compression monotonic tests are presented in this paper. A series of undrained triaxial tests were performed on Firoozkuh sand with various clay contents (Kaolinit with PI=12) under isotropic consolidation stress in order to investigate the undrained behaviour of clayey sands. The sand specimens had clay contents ranging from 0% to 30%. It was observed that the strength of specimens, in compression tests, decreases by increasing the clay content up to 30%.

firoozkooh sand, monotonic triaxial test, isotropic consolidation stress ,clay,undrained behaviour