On the potential effects of entrained air in centrifuge static liquefaction studies
On the potential effects of entrained air in centrifuge static liquefaction studies
Recent tailings storage facility and water dam failures have placed increased focus on static liquefaction, driving revisions to standards and guidelines along with more research into the triggering mechanism. One avenue of research has been application of geotechnical centrifuges to the study of the static liquefaction potential of slopes of loose soils or tailings. Much of this research has involved the study of the constant shear drained (CSD) mechanism, produced through the raising of the water level within a slope. Further, most recent studies appear to use viscous fluid to achieve hydraulic similitude, often without de-airing the fluid. Given the relatively low pore pressures present in the areas of slopes with highest stress ratio (i.e. near the toe), and existing awareness of the effects of entrained air on contractive soil response of loose samples sheared at constant water content, further investigation of the effect of entrained air on static liquefaction triggering of a CSD stress path is warranted. The current study investigates the effect of entrained air on the mechanical response of centrifuge tests by examining two centrifuge experiments featuring the CSD stress path within slopes of sand that appear to have failed under a higher phreatic surface (and, thus, higher stress ratios) than would typically be expected from element tests on the same material and field-scale examples. The response of these models is then investigated by means of CSD triaxial tests carried out under flushing and back pressure conditions, showing promising agreement.
David Reid; V. Kunasegaram; Andy Fourie
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Session 2: Scaling laws and fundamentals
https://doi.org/10.53243/ICPMG2026-221