The inabilities to measure volume change, to simulate overburden pressure, and to continually monitor water content without disassembling of the apparatus are among the limitations of pressure plate devices commonly used to experimentally apply matricsuction to a soil. These limitations affect the experimental determination of soil-water characteristic curves (SWCCs). The authors have developed a device that has greater flexibility with regard to applying matric suction and following a variety of net normal stress paths. The stainless steel cell is called the 'Fredlund SWCC' device and it allows the application of field overburden pressures for specimens up to 75 mm in diameter. The specimen volume change and water content can be continuously measured without dismantling the device. The device can measure both the drying and wetting SWCCs. The apparatus also allows for measurement of diffused air, removal of diffused air, and pressure compensation on the loading shaft. Also, the Fredlund SWCC device can be used for the measurement of in situ suction on undisturbed or compacted specimens. Details of the device and examples of data generated are presented in this paper. The versatility and flexibility exhibited by the device allow practitioners and researchers to conveniently and efficiently measure the SWCC that can then be used for the determination of unsaturated soil property functions.
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