TEACHING SEDIMENT TRANSPORT CONCEPTS USING SIMPLE, BENCH-TOP LABORATORY EXPERIMENTS

Understanding sediment transport is important for students in many areas of geosciences, including sedimentology, stratigraphy, geomorphology, and marine/coastal science. While experimental flumes are often used to demonstrate sediment transport concepts, they are not available or practical in many settings. In this poster, three simple laboratory exercises that explore aspects of critical shear stress, settling velocity, and suspended sediment transport are presented. Each of the exercises can be done in classroom settings with minimal equipment and can be geared toward introductory or more advanced students. A clipboard onto which a “fixed bed” of glass beads has been glued is used by students to explore how and why critical shear stresses for heterogeneous mixtures of sediment differ from those for homogeneous beds as predicted by the Shields relationship. The effects of viscosity and particle shape on settling velocity are investigated using polymer clay and a variety of fluids at different temperatures. Suspended sediment concentration profiles for different shear stresses and particle size distributions are measured in graduated cylinders using two different approaches and are compared. The experiments give students hands-on experience with sediment transport processes and the application of sediment transport equations, as well as reinforce the importance of replication to experimental design.