Abstract: A Conventional triaxial cell was modified in order to measure the pore water pressure and tocontrol the pore air pressure on unsaturated soil specimens,The results were compared and checkedwith those obtained by the“axial translation technique”.The measurement of the change in suction wasperformed in air drained triaxial shear tests with the modified cell and“axial translation technique”.ItiS found that suctions in the specimen are considerably influenced by the cell pressure and shearingstrain.