Development of a transparent layered model for the study of pile-supported embankments on soft soils

This study focuses on the construction process and challenges of a transparent, layered, two-dimensional physical model. The model was developed to enhance the comprehension of the mechanisms governing the behaviour of pile-supported embankments constructed over soft foundation soils. The methodology employed two types of ‘transparent soil’ techniques. Fused quartz particles, combined with a matching pore liquid, were utilised as the embankment base fill, while Laponite RD served as a surrogate for soft clay foundation conditions. The physical modelling techniques developed in this study were deemed suitable for advancing our understanding of internal deformations and the complexities of load transfer mechanisms in granular embankments over soft soils. These techniques not only provided observational results but also facilitated the quantification of shear, horizontal, and vertical strains. The findings of this study elucidate that the arching effect within the embankment’s granular base fill resulted in the transfer of 80% of the applied stress to the piles. This arching efficiency remained consistent with increases in surcharge. The identified arching mechanism was related to the development of primary sub-vertical shear bands within the embankment base, complemented by a secondary triangular shear band.