Influence of hydraulic flow regime on backward erosion piping

Abstract

Predicting piping failure is essential for assessing dike and dam safety. To improve the current description of internal erosion, we sought to evaluate the effects of laminar and turbulent flow on the transport of particles, which is lacking in existing assessment manuals. These insights are necessary to develop engineering tools to predict piping caused by seepage-induced backward erosion in loose sediment inside or below the dike or dam body. Particle transport occurs when there is an imbalance between the wall shear stress of the water in the pipe and the critical wall shear stress of the material. Here, we focus on pipe erosion beneath clayey dikes and impermeable dams, where piping is governed solely by the flow resistance in the pipes. We describe pipe properties, flow characteristics and turbulence intensities in relation to existing hypotheses from the literature.