Influence of Pile Geometry on Internal Sand Displacement around a Laterally Loaded Pile Using Transparent Soil

The influence of pile geometry on internal sand movement around a laterally loaded pile was visualized in this paper by utilizing transparent soil and digital image correlation (DIC) methods. Transparent sand was made of amorphous silica gel and a pore fluid with a matching refractive index. An optical system consisting of a laser light, a camera, a loading frame, and a computer was developed to illuminate a targeted section inside a transparent soil model. A distinctive laser speckle pattern was generated by the interaction between the laser light and transparent soil. Two laser speckle images before and after deformation were used to calculate the displacement field using DIC. Two different cross-sectioned piles were used in the tests: a square-sectioned pile and a circular pile. Both piles were made of acrylic and had a diameter or width of 12.7 mm. Two different failure planes were observed in the tests, where a larger zone was mobilized by the circular pile compared to the one in the square-sectioned pile.