Applied Research Using a Transparent Material with Hydraulic Properties Similar to Soil

An innovative material, transparent soil, was used to study flow from a prefabricated vertical drain (PVD). Transparent soil is a mixture of mineral oil, solvent, and amorphous silica. Before using the material to study PVD flow patterns, testing was completed to verify previously published values for hydraulic conductivity and porosity. The results of the independent testing matched the published results well. Experiments using scaled-down and full-size PVDs were completed in cells with diameters ranging from 10.2 to 30.0 cm, respectively. The results of these tests compared favorably to those obtained using an electrical analog and a mathematical model. The transparent soil was an acceptable representation of soil; however, degradations in transparency can be a problem in larger samples. Some other difficulties in using transparent soil, such as finding acceptable sealants and preventing dying of the silica particles, are discussed. In addition, recommended areas of continued research are presented.