A parametric theory of isotropic consolidation for saturated geomaterials with compressible phases. (May 2020)

• Record Type: Journal Article
• Authors: Szalwinski, Chris M.; Najma, Alireza; Sharma, Jitendra
• Is Part Of: Computers and geotechnics. Volume 121(2020)
• Publication Date: 2020-05
• Subjects: Pore pressure -- Variable porosity -- Coefficient of fluid content -- Pore flux coefficient -- Phase compressibilities -- Consolidation; Engineering geology -- Data processing -- Periodicals; Soil mechanics -- Data processing -- Periodicals; Rock mechanics -- Data processing -- Periodicals; 624.1510285
• DOI: 10.1016/j.compgeo.2019.103371
• Languages: English
• ISSNs: 0266-352X

Abstract

Abstract: Theories of isotropic consolidation for geomaterials with compressible phases require two loading tests: a full-drainage test at constant pore-pressure and a mixture test in which pore-pressure varies. In a no-drainage mixture test, the pore-pressure change falls short of the confining pressure change. In the unjacketed mixture test, the pore-pressure and confining pressure rates are equal. This paper develops a parametric theory that supports extrapolation of unjacketed bulk compressibility from the compressibilities measured in the full-drainage and mixture tests, elaborates and clarifies the isotropic version of the Biot and Willis theory of consolidation and expresses the unjacketed pore compressibilities of several sandstones in a combination of macroscopic and mesoscopic terms. The mesoscopic model includes solid and fluid phase compressibilities and phase-pressure distribution ratios. The coefficient of fluid content is identified as the product of porosity and the pore flux coefficient. The compressibility-induced component of the strain-rate in an unjacketed test is postulated to be an objective measure. This solution provides a framework for geotechnical modelling software that simulate the effect of porosity variation due to consolidation. With this theory, engineers can infer the phase-pressure distribution ratios from the measured Brown-Korringa compressibilities and represent the effects of both meso-heterogeneity and solid-grain rearrangement in constitutive models.