Simulation of pore pressures in triaxial creep tests
Date of Original Version
The finite element method is used to investigate the pore pressure response of a fine-grained, low permeability deep sea clay in triaxial creep tests, where the sample is subjected to compression and shearing with axisymmetric drainage. Following loading, the pore pressures dissipate rapidly near the drainage boundaries, but initially continue to increase at internal locations due to the Mandel-Cryer effect. Maximum excess pore pressures fall within the theoretical range of values predicted by Cryer (1963) for an elastic material. Overall, pore pressures and deformations during primary consolidation are affected slightly by the secondary compression parameter in Taylor's (1942) creep equation. Creep is found to decrease the rate at which pore pressure dissipation takes place compared to the no-creep case. Deformation of the triaxial specimen, particularly during the shearing phase, agrees with test results and further supports the constitutive model chosen. This type of modeling is useful in preparing loading schedules for drained tests that minimize excess pore pressures and preserve uniform effective stresses.
Geotechnical Special Publication
Brandes, Horst G., and Armand J. Silva. "Simulation of pore pressures in triaxial creep tests." Geotechnical Special Publication , 61 (1996): 96-104. https://digitalcommons.uri.edu/cve_facpubs/291