Volume Change Measurement of Soil Specimen in Triaxial Test

Measuring the volume change of a soil specimen during a test has become a standard routine in laboratory testing. Accurate volume change measurement does not depend solely on the resolution of the measurement devices used but also on other factors such as the measurement method, cell pressure, temperature fluctuations, system creep, and system compliance. This paper examines volume change measurement inferred from the volume of the confining water in a triaxial cell. In particular, the effects of stiffness of the pressure cell and temperature fluctuations on the accuracy of the volume change measurements are investigated. A method to correct for temperature effects on the volume of water in a triaxial pressure cell for providing a more reliable measurement of the volume change of a soil specimen is suggested. The suggested method can also be applied in triaxial apparatuses using double cells.