Volume change measurement in triaxial testing of unsaturated soils

2012-06-30
Ahmadinaghadeh, Reza
Toker, Nabi Kartal
Change in the volume of a soil specimen is related to its pore-fluid. In saturated soils, volume change can be measured by monitoring the inflow or outflow of pore water from the specimen. However, conventional techniques of measuring the volume change are not applicable to unsaturated soil specimens due to presence of air phase. Over the past decades, several volume measurement techniques have been developed for testing of unsaturated soils. This paper first summarizes basic working principles of different volume change measurement techniques used in triaxial apparatuses. Advantages and disadvantages of these measurement methods are debated, based on the most-recent literature. Finally, the technique that is most implementable to the commercial practice, namely cell liquid variation technique, is investigated at greater depth. The performance of this technique is experimentally observed by applying it to a saturated specimen, in a fully automated triaxial apparatus without any modification to the equipment. In these experiments, volume change during consolidation and shearing is measured by variation in cell liquid and compared to simultaneous measurements of change in pore water volume. A modification to the calibration procedure is proposed. The accuracy of the volume change measurements is demonstrated to improve with the modified procedure.
3 rd International Conference on New Developments in Soil Mechanics and Geotechnical Engineering, 2012

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Citation Formats
R. Ahmadinaghadeh and N. K. Toker, “Volume change measurement in triaxial testing of unsaturated soils,” presented at the 3 rd International Conference on New Developments in Soil Mechanics and Geotechnical Engineering, 2012, Nicosia, 2012, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/78843.