An Oedometer-Type Pressure Plate SWCC Apparatus

Abstract

Abstract A new oedometer device for SWCC determination has been evaluated by testing a wide range of soil types, and recommendations for best practices for use of this device have been made. The new device allows application and control of the net normal stress, σ−ua, in addition to the matric suction, ua−uw. Thus it can be used to simulate a range of overburden stresses and various other stress states of interest. It also allows the measurement of specimen volume change and the use of a single specimen for determination of the SWCC. The evaluation includes issues of temperature control, air diffusion through high air entry ceramic disks, and study of potential sources of error in water content determination for the SWCC. It is concluded that the new oedometer device can be used to obtain an accurate SWCC for a single specimen up to 1500kPa. General recommendations for appropriate use of the equipment and corrections to SWCC data obtained using axis translation pressure plate-type devices are made.