Transparent soils turn 25: Past, present, and future

Transparent soils debuted in 1993. Since their introduction, they have established their utility as a useful tool for physical modelling of (1) soil-structure interaction, (2) saturated-unsaturated hydraulic behavior, and (3) thermal processes in soils. This paper traces the history of the development of transparent soil surrogates and provides a brief literature review to aid new users interested in adopting transparent soils for use in laboratory 1g bench-scale and centrifuge tests to investigate a variety of geotechnical applications. The paper also looks to the future to anticipate where further developments in these materials and complementary technologies may be expected.