Linking geomechanical characteristics of soil with erosion of steep shore and recession of bluff

Abstract:

Bluffs are composed of materials that demonstrate heterogeneity in their composition and mechanical strength, leading to varying erosion and recession patterns. We present the results of our laboratory experiments investigating how changes in soil properties influence the erosion of steep beaches and recession of bluffs exposed to wave and surge. Phases of foreshore erosion and downcutting, slope failure and sediment deposition, offshore sediment transport and establishment of an equilibrium condition were quantified. The tendency of the beach profile to evolve into a concave up or concave down, depending on the material characteristics, are explained. It was found that soil composition and relative density are among the most influential parameters altering the erosional behavior of the bluff system.