Time Scaling Law for Two-stage Centrifuge Testing

ABSTRACT: The geotechnical centrifuge effectively models the self-weight consolidation of high-water content materials. However, concerns about material segregation arise when using centrifuge modelling due to the high-gravity application and the material's low yield strength. If a material segregates under the high gravity of the centrifuge but not under Earth's gravity, the model results may not accurately reflect the prototype behaviour. Two-stage centrifuge testing is sometimes employed to address this issue. In this method, the model initially spins at low gravity to increase solids content and yield stress before higher gravity is applied. While this approach reduces the potential of segregation, it necessitates new time-scaling laws so that both stages realistically represent the same prototype. This paper presents time-scaling laws for calculating prototype times in two-stage centrifuge testing, and it also provides centrifuge testing and numerical modelling results for validating the scaling law.